# kb

id: utf-8-glossary-mdn-20260505-0
file: data/developer.mozilla.org/en-US/docs/Glossary/UTF-8-0.md
category: reference
title: UTF-8 - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/UTF-8
date_saved: 2026-05-05T05:48:02.195471+00:00
instance: kb-cron
parent: utf-8-glossary-mdn-20260505-0
summary:
* [Skip to main content](https://developer.mozilla.org/en-US/docs/Glossary/UTF-8#content) * [Skip to search](https://developer.mozilla.org/en-US/docs/Glossary/UTF-8#search) [ MDN ](https://developer.mozilla.org/en-US/) HTML [HTML: Markup language](https://developer.mozilla.org/en-US/docs/Web/HTML) HTML reference * [Elements](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements) * [Global attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes) * [Attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Attributes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference "See all HTML references") HTML guides * [Responsive images](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Responsive_images) * [HTML cheatsheet](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Cheatsheet) * [Date & time formats](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Date_and_time_formats) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides "See all HTML guides") Markup languages * [SVG](https://developer.mozilla.org/en-US/docs/Web/SVG) * [MathML](https://developer.mozilla.org/en-US/docs/Web/MathML) * [XML](https://developer.mozilla.org/en-US/docs/Web/XML) CSS [CSS: Styling language](https://developer.mozilla.org/en-US/docs/Web/CSS) CSS reference * [Properties](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties) * [Selectors](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors) * [At-rules](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/At-rules) * [Values](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference "See all CSS references") CSS guides * [Box model](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Box_model/Introduction) * [Animations](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Animations/Using) * [Flexbox](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Flexible_box_layout/Basic_concepts) * [Colors](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Colors/Applying_color) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides "See all CSS guides") Layout cookbook * [Column layouts](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Column_layouts) * [Centering an element](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Center_an_element) * [Card component](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Card) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook) JavaScriptJS [JavaScript: Scripting language](https://developer.mozilla.org/en-US/docs/Web/JavaScript) JS reference * [Standard built-in objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects) * [Expressions & operators](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators) * [Statements & declarations](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements) * [Functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference "See all JavaScript references") JS guides * [Control flow & error handing](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Control_flow_and_error_handling) * [Loops and iteration](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration) * [Working with objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_objects) * [Using classes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_classes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide "See all JavaScript guides") Web APIs [Web APIs: Programming interfaces](https://developer.mozilla.org/en-US/docs/Web/API) Web API reference * [File system API](https://developer.mozilla.org/en-US/docs/Web/API/File_System_API) * [Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) * [Geolocation API](https://developer.mozilla.org/en-US/docs/Web/API/Geolocation_API) * [HTML DOM API](https://developer.mozilla.org/en-US/docs/Web/API/HTML_DOM_API) * [Push API](https://developer.mozilla.org/en-US/docs/Web/API/Push_API) * [Service worker API](https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API) * [See all…](https://developer.mozilla.org/en-US/docs/Web/API


id: utf-8-glossary-mdn-20260505-1
file: data/developer.mozilla.org/en-US/docs/Glossary/UTF-8-1.md
category: reference
title: UTF-8 - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/UTF-8
date_saved: 2026-05-05T05:48:02.195471+00:00
instance: kb-cron
parent: utf-8-glossary-mdn-20260505-0
summary:
## Help improve MDN [Learn how to contribute](https://developer.mozilla.org/en-US/docs/MDN/Community/Getting_started) This page was last modified on Jul 11, 2025 by [MDN contributors](https://developer.mozilla.org/en-US/docs/Glossary/UTF-8/contributors.txt). [View this page on GitHub](https://github.com/mdn/content/blob/main/files/en-us/glossary/utf-8/index.md?plain=1 "Folder: en-us/glossary/utf-8 \(Opens in a new tab\)") • [Report a problem with this content](https://github.com/mdn/content/issues/new?template=page-report.yml&mdn-url=https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FUTF-8&metadata=%3C%21--+Do+not+make+changes+below+this+line+--%3E%0A%3Cdetails%3E%0A%3Csummary%3EPage+report+details%3C%2Fsummary%3E%0A%0A*+Folder%3A+%60en-us%2Fglossary%2Futf-8%60%0A*+MDN+URL%3A+https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FUTF-8%0A*+GitHub+URL%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fblob%2Fmain%2Ffiles%2Fen-us%2Fglossary%2Futf-8%2Findex.md%0A*+Last+commit%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fcommit%2F2547f622337d6cbf8c3794776b17ed377d6aad57%0A*+Document+last+modified%3A+2025-07-11T14%3A45%3A59.000Z%0A%0A%3C%2Fdetails%3E "This will take you to GitHub to file a new issue.") 1. [Glossary](https://developer.mozilla.org/en-US/docs/Glossary) 2. 1. [Abstraction](https://developer.mozilla.org/en-US/docs/Glossary/Abstraction) 2. [Accent](https://developer.mozilla.org/en-US/docs/Glossary/Accent) 3. [Accessibility](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility) 4. [Accessibility tree](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility_tree) 5. [Accessible description](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_description) 6. [Accessible name](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_name) 7. [Adobe Flash](https://developer.mozilla.org/en-US/docs/Glossary/Adobe_Flash) 8. [Advance measure](https://developer.mozilla.org/en-US/docs/Glossary/Advance_measure) 9. [Ajax](https://developer.mozilla.org/en-US/docs/Glossary/AJAX) 10. [Algorithm](https://developer.mozilla.org/en-US/docs/Glossary/Algorithm) 11. [Alignment container](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Container) 12. [Alignment subject](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Subject) 13. [Alpha (alpha channel)](https://developer.mozilla.org/en-US/docs/Glossary/Alpha) 14. [ALPN](https://developer.mozilla.org/en-US/docs/Glossary/ALPN) 15. [API](https://developer.mozilla.org/en-US/docs/Glossary/API) 16. [Apple Safari](https://developer.mozilla.org/en-US/docs/Glossary/Apple_Safari) 17. [Application context](https://developer.mozilla.org/en-US/docs/Glossary/Application_context) 18. [Argument](https://developer.mozilla.org/en-US/docs/Glossary/Argument) 19. [ARIA](https://developer.mozilla.org/en-US/docs/Glossary/ARIA) 20. [ARPA](https://developer.mozilla.org/en-US/docs/Glossary/ARPA) 21. [ARPANET](https://developer.mozilla.org/en-US/docs/Glossary/Arpanet) 22. [Array](https://developer.mozilla.org/en-US/docs/Glossary/Array) 23. [ASCII](https://developer.mozilla.org/en-US/docs/Glossary/ASCII) 24. [Aspect ratio](https://developer.mozilla.org/en-US/docs/Glossary/Aspect_ratio) 25. [Asynchronous](https://developer.mozilla.org/en-US/docs/Glossary/Asynchronous) 26. [ATAG](https://developer.mozilla.org/en-US/docs/Glossary/ATAG) 27. [Attribute](https://developer.mozilla.org/en-US/docs/Glossary/Attribute) 28. [Authentication](https://developer.mozilla.org/en-US/docs/Glossary/Authentication) 29. [Authenticator](https://developer.mozilla.org/en-US/docs/Glossary/Authenticator) 30. [Bandwidth](https://developer.mozilla.org/en-US/docs/Glossary/Bandwidth) 31. [Base64](https://developer.mozilla.org/en-US/docs/Glossary/Base64) 32. [Baseline](https://developer.mozilla.org/en-US/docs/Glossary/Baseline) 1. [Baseline (compatibility)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Compatibility) 2. [Baseline (typography)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Typography) 33. [BCP 47 language tag](https://developer.mozilla.org/en-US/docs/Glossary/BCP_47_language_tag) 34. [Beacon](https://developer.mozilla.org/en-US/docs/Glossary/Beacon) 35. [Bézier curve](https://developer.mozilla.org/en-US/docs/Glossary/Bezier_curve) 36. [bfcache](https://developer.mozilla.org/en-US/docs/Glossary/bfcache) 37. [BiDi](https://developer.mozilla.org/en-US/docs/Glossary/BiDi) 38. [BigInt](https://developer.mozilla.org/en-US/docs/Glossary/BigInt) 39. [Binding](https://developer.mozilla.org/en-US/docs/Glossary/Binding) 40. [Bitwise flags](https://developer.mozilla.org/en-US/docs/Glossary/Bitwise_flags) 41. [Blink](https://developer.mozilla.org/en-US/docs/Glossary/Blink) 42. [blink element (<blink> tag)](https://developer.mozilla.org/en-US/docs/Glossary/blink_element) 43. [Block](https://developer.mozilla.org/en-US/docs/Glossary/Block) 1. [Block (CSS)](https://developer.mozilla.org/en-US/docs/Glossary/Block/CSS) 2. [Block (scripting)](https://developer.mozilla.org/en-US/docs/Glossary/Block/Scripting) 44. [Block cipher mode of operation](https://developer.mozilla.org/en-US/docs/Glossary/Block_cipher_mode_of_operation) 45. [Block-level content](https://developer.mozilla.org/en-US/docs/Glossary/Block-level_content) 46. [Boolean](https://developer.mozilla.org/en-US/docs/Glossary/Boolean) 1. [Boolean (JavaScript)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/JavaScript) 2. [Boolean attribute (ARIA)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/ARIA) 3. [Boolean attribute (HTML)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/HTML) 47. [Bounding box](https://developer.mozilla.org/en-US/docs/Glossary/Bounding_box) 48. [Breadcrumb](https://developer.mozilla.org/en-US/docs/Glossary/Breadcrumb) 49. [Brotli


id: uuid-glossary-mdn-20260505-0
file: data/developer.mozilla.org/en-US/docs/Glossary/UUID-0.md
category: reference
title: UUID - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/UUID
date_saved: 2026-05-05T05:48:04.543299+00:00
instance: kb-cron
parent: uuid-glossary-mdn-20260505-0
summary:
* [Skip to main content](https://developer.mozilla.org/en-US/docs/Glossary/UUID#content) * [Skip to search](https://developer.mozilla.org/en-US/docs/Glossary/UUID#search) [ MDN ](https://developer.mozilla.org/en-US/) HTML [HTML: Markup language](https://developer.mozilla.org/en-US/docs/Web/HTML) HTML reference * [Elements](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements) * [Global attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes) * [Attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Attributes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference "See all HTML references") HTML guides * [Responsive images](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Responsive_images) * [HTML cheatsheet](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Cheatsheet) * [Date & time formats](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Date_and_time_formats) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides "See all HTML guides") Markup languages * [SVG](https://developer.mozilla.org/en-US/docs/Web/SVG) * [MathML](https://developer.mozilla.org/en-US/docs/Web/MathML) * [XML](https://developer.mozilla.org/en-US/docs/Web/XML) CSS [CSS: Styling language](https://developer.mozilla.org/en-US/docs/Web/CSS) CSS reference * [Properties](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties) * [Selectors](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors) * [At-rules](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/At-rules) * [Values](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference "See all CSS references") CSS guides * [Box model](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Box_model/Introduction) * [Animations](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Animations/Using) * [Flexbox](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Flexible_box_layout/Basic_concepts) * [Colors](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Colors/Applying_color) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides "See all CSS guides") Layout cookbook * [Column layouts](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Column_layouts) * [Centering an element](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Center_an_element) * [Card component](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Card) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook) JavaScriptJS [JavaScript: Scripting language](https://developer.mozilla.org/en-US/docs/Web/JavaScript) JS reference * [Standard built-in objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects) * [Expressions & operators](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators) * [Statements & declarations](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements) * [Functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference "See all JavaScript references") JS guides * [Control flow & error handing](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Control_flow_and_error_handling) * [Loops and iteration](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration) * [Working with objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_objects) * [Using classes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_classes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide "See all JavaScript guides") Web APIs [Web APIs: Programming interfaces](https://developer.mozilla.org/en-US/docs/Web/API) Web API reference * [File system API](https://developer.mozilla.org/en-US/docs/Web/API/File_System_API) * [Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) * [Geolocation API](https://developer.mozilla.org/en-US/docs/Web/API/Geolocation_API) * [HTML DOM API](https://developer.mozilla.org/en-US/docs/Web/API/HTML_DOM_API) * [Push API](https://developer.mozilla.org/en-US/docs/Web/API/Push_API) * [Service worker API](https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API) * [See all…](https://developer.mozilla.org/en-US/docs/Web/API


id: uuid-glossary-mdn-20260505-1
file: data/developer.mozilla.org/en-US/docs/Glossary/UUID-1.md
category: reference
title: UUID - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/UUID
date_saved: 2026-05-05T05:48:04.543299+00:00
instance: kb-cron
parent: uuid-glossary-mdn-20260505-0
summary:
## Help improve MDN [Learn how to contribute](https://developer.mozilla.org/en-US/docs/MDN/Community/Getting_started) This page was last modified on Jul 11, 2025 by [MDN contributors](https://developer.mozilla.org/en-US/docs/Glossary/UUID/contributors.txt). [View this page on GitHub](https://github.com/mdn/content/blob/main/files/en-us/glossary/uuid/index.md?plain=1 "Folder: en-us/glossary/uuid \(Opens in a new tab\)") • [Report a problem with this content](https://github.com/mdn/content/issues/new?template=page-report.yml&mdn-url=https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FUUID&metadata=%3C%21--+Do+not+make+changes+below+this+line+--%3E%0A%3Cdetails%3E%0A%3Csummary%3EPage+report+details%3C%2Fsummary%3E%0A%0A*+Folder%3A+%60en-us%2Fglossary%2Fuuid%60%0A*+MDN+URL%3A+https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FUUID%0A*+GitHub+URL%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fblob%2Fmain%2Ffiles%2Fen-us%2Fglossary%2Fuuid%2Findex.md%0A*+Last+commit%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fcommit%2F2547f622337d6cbf8c3794776b17ed377d6aad57%0A*+Document+last+modified%3A+2025-07-11T14%3A45%3A59.000Z%0A%0A%3C%2Fdetails%3E "This will take you to GitHub to file a new issue.") 1. [Glossary](https://developer.mozilla.org/en-US/docs/Glossary) 2. 1. [Abstraction](https://developer.mozilla.org/en-US/docs/Glossary/Abstraction) 2. [Accent](https://developer.mozilla.org/en-US/docs/Glossary/Accent) 3. [Accessibility](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility) 4. [Accessibility tree](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility_tree) 5. [Accessible description](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_description) 6. [Accessible name](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_name) 7. [Adobe Flash](https://developer.mozilla.org/en-US/docs/Glossary/Adobe_Flash) 8. [Advance measure](https://developer.mozilla.org/en-US/docs/Glossary/Advance_measure) 9. [Ajax](https://developer.mozilla.org/en-US/docs/Glossary/AJAX) 10. [Algorithm](https://developer.mozilla.org/en-US/docs/Glossary/Algorithm) 11. [Alignment container](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Container) 12. [Alignment subject](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Subject) 13. [Alpha (alpha channel)](https://developer.mozilla.org/en-US/docs/Glossary/Alpha) 14. [ALPN](https://developer.mozilla.org/en-US/docs/Glossary/ALPN) 15. [API](https://developer.mozilla.org/en-US/docs/Glossary/API) 16. [Apple Safari](https://developer.mozilla.org/en-US/docs/Glossary/Apple_Safari) 17. [Application context](https://developer.mozilla.org/en-US/docs/Glossary/Application_context) 18. [Argument](https://developer.mozilla.org/en-US/docs/Glossary/Argument) 19. [ARIA](https://developer.mozilla.org/en-US/docs/Glossary/ARIA) 20. [ARPA](https://developer.mozilla.org/en-US/docs/Glossary/ARPA) 21. [ARPANET](https://developer.mozilla.org/en-US/docs/Glossary/Arpanet) 22. [Array](https://developer.mozilla.org/en-US/docs/Glossary/Array) 23. [ASCII](https://developer.mozilla.org/en-US/docs/Glossary/ASCII) 24. [Aspect ratio](https://developer.mozilla.org/en-US/docs/Glossary/Aspect_ratio) 25. [Asynchronous](https://developer.mozilla.org/en-US/docs/Glossary/Asynchronous) 26. [ATAG](https://developer.mozilla.org/en-US/docs/Glossary/ATAG) 27. [Attribute](https://developer.mozilla.org/en-US/docs/Glossary/Attribute) 28. [Authentication](https://developer.mozilla.org/en-US/docs/Glossary/Authentication) 29. [Authenticator](https://developer.mozilla.org/en-US/docs/Glossary/Authenticator) 30. [Bandwidth](https://developer.mozilla.org/en-US/docs/Glossary/Bandwidth) 31. [Base64](https://developer.mozilla.org/en-US/docs/Glossary/Base64) 32. [Baseline](https://developer.mozilla.org/en-US/docs/Glossary/Baseline) 1. [Baseline (compatibility)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Compatibility) 2. [Baseline (typography)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Typography) 33. [BCP 47 language tag](https://developer.mozilla.org/en-US/docs/Glossary/BCP_47_language_tag) 34. [Beacon](https://developer.mozilla.org/en-US/docs/Glossary/Beacon) 35. [Bézier curve](https://developer.mozilla.org/en-US/docs/Glossary/Bezier_curve) 36. [bfcache](https://developer.mozilla.org/en-US/docs/Glossary/bfcache) 37. [BiDi](https://developer.mozilla.org/en-US/docs/Glossary/BiDi) 38. [BigInt](https://developer.mozilla.org/en-US/docs/Glossary/BigInt) 39. [Binding](https://developer.mozilla.org/en-US/docs/Glossary/Binding) 40. [Bitwise flags](https://developer.mozilla.org/en-US/docs/Glossary/Bitwise_flags) 41. [Blink](https://developer.mozilla.org/en-US/docs/Glossary/Blink) 42. [blink element (<blink> tag)](https://developer.mozilla.org/en-US/docs/Glossary/blink_element) 43. [Block](https://developer.mozilla.org/en-US/docs/Glossary/Block) 1. [Block (CSS)](https://developer.mozilla.org/en-US/docs/Glossary/Block/CSS) 2. [Block (scripting)](https://developer.mozilla.org/en-US/docs/Glossary/Block/Scripting) 44. [Block cipher mode of operation](https://developer.mozilla.org/en-US/docs/Glossary/Block_cipher_mode_of_operation) 45. [Block-level content](https://developer.mozilla.org/en-US/docs/Glossary/Block-level_content) 46. [Boolean](https://developer.mozilla.org/en-US/docs/Glossary/Boolean) 1. [Boolean (JavaScript)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/JavaScript) 2. [Boolean attribute (ARIA)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/ARIA) 3. [Boolean attribute (HTML)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/HTML) 47. [Bounding box](https://developer.mozilla.org/en-US/docs/Glossary/Bounding_box) 48. [Breadcrumb](https://developer.mozilla.org/en-US/docs/Glossary/Breadcrumb) 49. [Brotli


id: ux-glossary-mdn-20260505-0
file: data/developer.mozilla.org/en-US/docs/Glossary/UX-0.md
category: reference
title: UX - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/UX
date_saved: 2026-05-05T05:48:07.212904+00:00
instance: kb-cron
parent: ux-glossary-mdn-20260505-0
summary:
* [Skip to main content](https://developer.mozilla.org/en-US/docs/Glossary/UX#content) * [Skip to search](https://developer.mozilla.org/en-US/docs/Glossary/UX#search) [ MDN ](https://developer.mozilla.org/en-US/) HTML [HTML: Markup language](https://developer.mozilla.org/en-US/docs/Web/HTML) HTML reference * [Elements](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements) * [Global attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes) * [Attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Attributes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference "See all HTML references") HTML guides * [Responsive images](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Responsive_images) * [HTML cheatsheet](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Cheatsheet) * [Date & time formats](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Date_and_time_formats) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides "See all HTML guides") Markup languages * [SVG](https://developer.mozilla.org/en-US/docs/Web/SVG) * [MathML](https://developer.mozilla.org/en-US/docs/Web/MathML) * [XML](https://developer.mozilla.org/en-US/docs/Web/XML) CSS [CSS: Styling language](https://developer.mozilla.org/en-US/docs/Web/CSS) CSS reference * [Properties](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties) * [Selectors](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors) * [At-rules](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/At-rules) * [Values](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference "See all CSS references") CSS guides * [Box model](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Box_model/Introduction) * [Animations](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Animations/Using) * [Flexbox](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Flexible_box_layout/Basic_concepts) * [Colors](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Colors/Applying_color) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides "See all CSS guides") Layout cookbook * [Column layouts](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Column_layouts) * [Centering an element](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Center_an_element) * [Card component](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Card) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook) JavaScriptJS [JavaScript: Scripting language](https://developer.mozilla.org/en-US/docs/Web/JavaScript) JS reference * [Standard built-in objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects) * [Expressions & operators](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators) * [Statements & declarations](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements) * [Functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference "See all JavaScript references") JS guides * [Control flow & error handing](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Control_flow_and_error_handling) * [Loops and iteration](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration) * [Working with objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_objects) * [Using classes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_classes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide "See all JavaScript guides") Web APIs [Web APIs: Programming interfaces](https://developer.mozilla.org/en-US/docs/Web/API) Web API reference * [File system API](https://developer.mozilla.org/en-US/docs/Web/API/File_System_API) * [Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) * [Geolocation API](https://developer.mozilla.org/en-US/docs/Web/API/Geolocation_API) * [HTML DOM API](https://developer.mozilla.org/en-US/docs/Web/API/HTML_DOM_API) * [Push API](https://developer.mozilla.org/en-US/docs/Web/API/Push_API) * [Service worker API](https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API) * [See all…](https://developer.mozilla.org/en-US/docs/Web/API


id: ux-glossary-mdn-20260505-1
file: data/developer.mozilla.org/en-US/docs/Glossary/UX-1.md
category: reference
title: UX - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/UX
date_saved: 2026-05-05T05:48:07.212904+00:00
instance: kb-cron
parent: ux-glossary-mdn-20260505-0
summary:
## Help improve MDN [Learn how to contribute](https://developer.mozilla.org/en-US/docs/MDN/Community/Getting_started) This page was last modified on Dec 15, 2025 by [MDN contributors](https://developer.mozilla.org/en-US/docs/Glossary/UX/contributors.txt). [View this page on GitHub](https://github.com/mdn/content/blob/main/files/en-us/glossary/ux/index.md?plain=1 "Folder: en-us/glossary/ux \(Opens in a new tab\)") • [Report a problem with this content](https://github.com/mdn/content/issues/new?template=page-report.yml&mdn-url=https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FUX&metadata=%3C%21--+Do+not+make+changes+below+this+line+--%3E%0A%3Cdetails%3E%0A%3Csummary%3EPage+report+details%3C%2Fsummary%3E%0A%0A*+Folder%3A+%60en-us%2Fglossary%2Fux%60%0A*+MDN+URL%3A+https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FUX%0A*+GitHub+URL%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fblob%2Fmain%2Ffiles%2Fen-us%2Fglossary%2Fux%2Findex.md%0A*+Last+commit%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fcommit%2F7d4f930455a349e3c73836500add3d4840c76f5d%0A*+Document+last+modified%3A+2025-12-15T10%3A27%3A52.000Z%0A%0A%3C%2Fdetails%3E "This will take you to GitHub to file a new issue.") 1. [Glossary](https://developer.mozilla.org/en-US/docs/Glossary) 2. 1. [Abstraction](https://developer.mozilla.org/en-US/docs/Glossary/Abstraction) 2. [Accent](https://developer.mozilla.org/en-US/docs/Glossary/Accent) 3. [Accessibility](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility) 4. [Accessibility tree](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility_tree) 5. [Accessible description](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_description) 6. [Accessible name](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_name) 7. [Adobe Flash](https://developer.mozilla.org/en-US/docs/Glossary/Adobe_Flash) 8. [Advance measure](https://developer.mozilla.org/en-US/docs/Glossary/Advance_measure) 9. [Ajax](https://developer.mozilla.org/en-US/docs/Glossary/AJAX) 10. [Algorithm](https://developer.mozilla.org/en-US/docs/Glossary/Algorithm) 11. [Alignment container](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Container) 12. [Alignment subject](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Subject) 13. [Alpha (alpha channel)](https://developer.mozilla.org/en-US/docs/Glossary/Alpha) 14. [ALPN](https://developer.mozilla.org/en-US/docs/Glossary/ALPN) 15. [API](https://developer.mozilla.org/en-US/docs/Glossary/API) 16. [Apple Safari](https://developer.mozilla.org/en-US/docs/Glossary/Apple_Safari) 17. [Application context](https://developer.mozilla.org/en-US/docs/Glossary/Application_context) 18. [Argument](https://developer.mozilla.org/en-US/docs/Glossary/Argument) 19. [ARIA](https://developer.mozilla.org/en-US/docs/Glossary/ARIA) 20. [ARPA](https://developer.mozilla.org/en-US/docs/Glossary/ARPA) 21. [ARPANET](https://developer.mozilla.org/en-US/docs/Glossary/Arpanet) 22. [Array](https://developer.mozilla.org/en-US/docs/Glossary/Array) 23. [ASCII](https://developer.mozilla.org/en-US/docs/Glossary/ASCII) 24. [Aspect ratio](https://developer.mozilla.org/en-US/docs/Glossary/Aspect_ratio) 25. [Asynchronous](https://developer.mozilla.org/en-US/docs/Glossary/Asynchronous) 26. [ATAG](https://developer.mozilla.org/en-US/docs/Glossary/ATAG) 27. [Attribute](https://developer.mozilla.org/en-US/docs/Glossary/Attribute) 28. [Authentication](https://developer.mozilla.org/en-US/docs/Glossary/Authentication) 29. [Authenticator](https://developer.mozilla.org/en-US/docs/Glossary/Authenticator) 30. [Bandwidth](https://developer.mozilla.org/en-US/docs/Glossary/Bandwidth) 31. [Base64](https://developer.mozilla.org/en-US/docs/Glossary/Base64) 32. [Baseline](https://developer.mozilla.org/en-US/docs/Glossary/Baseline) 1. [Baseline (compatibility)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Compatibility) 2. [Baseline (typography)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Typography) 33. [BCP 47 language tag](https://developer.mozilla.org/en-US/docs/Glossary/BCP_47_language_tag) 34. [Beacon](https://developer.mozilla.org/en-US/docs/Glossary/Beacon) 35. [Bézier curve](https://developer.mozilla.org/en-US/docs/Glossary/Bezier_curve) 36. [bfcache](https://developer.mozilla.org/en-US/docs/Glossary/bfcache) 37. [BiDi](https://developer.mozilla.org/en-US/docs/Glossary/BiDi) 38. [BigInt](https://developer.mozilla.org/en-US/docs/Glossary/BigInt) 39. [Binding](https://developer.mozilla.org/en-US/docs/Glossary/Binding) 40. [Bitwise flags](https://developer.mozilla.org/en-US/docs/Glossary/Bitwise_flags) 41. [Blink](https://developer.mozilla.org/en-US/docs/Glossary/Blink) 42. [blink element (<blink> tag)](https://developer.mozilla.org/en-US/docs/Glossary/blink_element) 43. [Block](https://developer.mozilla.org/en-US/docs/Glossary/Block) 1. [Block (CSS)](https://developer.mozilla.org/en-US/docs/Glossary/Block/CSS) 2. [Block (scripting)](https://developer.mozilla.org/en-US/docs/Glossary/Block/Scripting) 44. [Block cipher mode of operation](https://developer.mozilla.org/en-US/docs/Glossary/Block_cipher_mode_of_operation) 45. [Block-level content](https://developer.mozilla.org/en-US/docs/Glossary/Block-level_content) 46. [Boolean](https://developer.mozilla.org/en-US/docs/Glossary/Boolean) 1. [Boolean (JavaScript)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/JavaScript) 2. [Boolean attribute (ARIA)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/ARIA) 3. [Boolean attribute (HTML)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/HTML) 47. [Bounding box](https://developer.mozilla.org/en-US/docs/Glossary/Bounding_box) 48. [Breadcrumb](https://developer.mozilla.org/en-US/docs/Glossary/Breadcrumb) 49. [Brotli


id: undefined-glossary-mdn-20260505-0
file: data/developer.mozilla.org/en-US/docs/Glossary/Undefined-0.md
category: reference
title: Undefined - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/Undefined
date_saved: 2026-05-05T05:48:09.574326+00:00
instance: kb-cron
parent: undefined-glossary-mdn-20260505-0
summary:
* [Skip to main content](https://developer.mozilla.org/en-US/docs/Glossary/Undefined#content) * [Skip to search](https://developer.mozilla.org/en-US/docs/Glossary/Undefined#search) [ MDN ](https://developer.mozilla.org/en-US/) HTML [HTML: Markup language](https://developer.mozilla.org/en-US/docs/Web/HTML) HTML reference * [Elements](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements) * [Global attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes) * [Attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Attributes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference "See all HTML references") HTML guides * [Responsive images](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Responsive_images) * [HTML cheatsheet](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Cheatsheet) * [Date & time formats](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Date_and_time_formats) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides "See all HTML guides") Markup languages * [SVG](https://developer.mozilla.org/en-US/docs/Web/SVG) * [MathML](https://developer.mozilla.org/en-US/docs/Web/MathML) * [XML](https://developer.mozilla.org/en-US/docs/Web/XML) CSS [CSS: Styling language](https://developer.mozilla.org/en-US/docs/Web/CSS) CSS reference * [Properties](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties) * [Selectors](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors) * [At-rules](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/At-rules) * [Values](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference "See all CSS references") CSS guides * [Box model](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Box_model/Introduction) * [Animations](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Animations/Using) * [Flexbox](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Flexible_box_layout/Basic_concepts) * [Colors](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Colors/Applying_color) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides "See all CSS guides") Layout cookbook * [Column layouts](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Column_layouts) * [Centering an element](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Center_an_element) * [Card component](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Card) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook) JavaScriptJS [JavaScript: Scripting language](https://developer.mozilla.org/en-US/docs/Web/JavaScript) JS reference * [Standard built-in objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects) * [Expressions & operators](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators) * [Statements & declarations](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements) * [Functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference "See all JavaScript references") JS guides * [Control flow & error handing](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Control_flow_and_error_handling) * [Loops and iteration](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration) * [Working with objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_objects) * [Using classes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_classes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide "See all JavaScript guides") Web APIs [Web APIs: Programming interfaces](https://developer.mozilla.org/en-US/docs/Web/API) Web API reference * [File system API](https://developer.mozilla.org/en-US/docs/Web/API/File_System_API) * [Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) * [Geolocation API](https://developer.mozilla.org/en-US/docs/Web/API/Geolocation_API) * [HTML DOM API](https://developer.mozilla.org/en-US/docs/Web/API/HTML_DOM_API) * [Push API](https://developer.mozilla.org/en-US/docs/Web/API/Push_API) * [Service worker API](https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API) * [See all…](https://developer.mozilla.org/en-US/docs/Web/API


id: undefined-glossary-mdn-20260505-1
file: data/developer.mozilla.org/en-US/docs/Glossary/Undefined-1.md
category: reference
title: Undefined - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/Undefined
date_saved: 2026-05-05T05:48:09.574326+00:00
instance: kb-cron
parent: undefined-glossary-mdn-20260505-0
summary:
## Help improve MDN [Learn how to contribute](https://developer.mozilla.org/en-US/docs/MDN/Community/Getting_started) This page was last modified on Jul 11, 2025 by [MDN contributors](https://developer.mozilla.org/en-US/docs/Glossary/Undefined/contributors.txt). [View this page on GitHub](https://github.com/mdn/content/blob/main/files/en-us/glossary/undefined/index.md?plain=1 "Folder: en-us/glossary/undefined \(Opens in a new tab\)") • [Report a problem with this content](https://github.com/mdn/content/issues/new?template=page-report.yml&mdn-url=https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FUndefined&metadata=%3C%21--+Do+not+make+changes+below+this+line+--%3E%0A%3Cdetails%3E%0A%3Csummary%3EPage+report+details%3C%2Fsummary%3E%0A%0A*+Folder%3A+%60en-us%2Fglossary%2Fundefined%60%0A*+MDN+URL%3A+https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FUndefined%0A*+GitHub+URL%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fblob%2Fmain%2Ffiles%2Fen-us%2Fglossary%2Fundefined%2Findex.md%0A*+Last+commit%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fcommit%2F2547f622337d6cbf8c3794776b17ed377d6aad57%0A*+Document+last+modified%3A+2025-07-11T14%3A45%3A59.000Z%0A%0A%3C%2Fdetails%3E "This will take you to GitHub to file a new issue.") 1. [Glossary](https://developer.mozilla.org/en-US/docs/Glossary) 2. 1. [Abstraction](https://developer.mozilla.org/en-US/docs/Glossary/Abstraction) 2. [Accent](https://developer.mozilla.org/en-US/docs/Glossary/Accent) 3. [Accessibility](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility) 4. [Accessibility tree](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility_tree) 5. [Accessible description](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_description) 6. [Accessible name](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_name) 7. [Adobe Flash](https://developer.mozilla.org/en-US/docs/Glossary/Adobe_Flash) 8. [Advance measure](https://developer.mozilla.org/en-US/docs/Glossary/Advance_measure) 9. [Ajax](https://developer.mozilla.org/en-US/docs/Glossary/AJAX) 10. [Algorithm](https://developer.mozilla.org/en-US/docs/Glossary/Algorithm) 11. [Alignment container](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Container) 12. [Alignment subject](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Subject) 13. [Alpha (alpha channel)](https://developer.mozilla.org/en-US/docs/Glossary/Alpha) 14. [ALPN](https://developer.mozilla.org/en-US/docs/Glossary/ALPN) 15. [API](https://developer.mozilla.org/en-US/docs/Glossary/API) 16. [Apple Safari](https://developer.mozilla.org/en-US/docs/Glossary/Apple_Safari) 17. [Application context](https://developer.mozilla.org/en-US/docs/Glossary/Application_context) 18. [Argument](https://developer.mozilla.org/en-US/docs/Glossary/Argument) 19. [ARIA](https://developer.mozilla.org/en-US/docs/Glossary/ARIA) 20. [ARPA](https://developer.mozilla.org/en-US/docs/Glossary/ARPA) 21. [ARPANET](https://developer.mozilla.org/en-US/docs/Glossary/Arpanet) 22. [Array](https://developer.mozilla.org/en-US/docs/Glossary/Array) 23. [ASCII](https://developer.mozilla.org/en-US/docs/Glossary/ASCII) 24. [Aspect ratio](https://developer.mozilla.org/en-US/docs/Glossary/Aspect_ratio) 25. [Asynchronous](https://developer.mozilla.org/en-US/docs/Glossary/Asynchronous) 26. [ATAG](https://developer.mozilla.org/en-US/docs/Glossary/ATAG) 27. [Attribute](https://developer.mozilla.org/en-US/docs/Glossary/Attribute) 28. [Authentication](https://developer.mozilla.org/en-US/docs/Glossary/Authentication) 29. [Authenticator](https://developer.mozilla.org/en-US/docs/Glossary/Authenticator) 30. [Bandwidth](https://developer.mozilla.org/en-US/docs/Glossary/Bandwidth) 31. [Base64](https://developer.mozilla.org/en-US/docs/Glossary/Base64) 32. [Baseline](https://developer.mozilla.org/en-US/docs/Glossary/Baseline) 1. [Baseline (compatibility)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Compatibility) 2. [Baseline (typography)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Typography) 33. [BCP 47 language tag](https://developer.mozilla.org/en-US/docs/Glossary/BCP_47_language_tag) 34. [Beacon](https://developer.mozilla.org/en-US/docs/Glossary/Beacon) 35. [Bézier curve](https://developer.mozilla.org/en-US/docs/Glossary/Bezier_curve) 36. [bfcache](https://developer.mozilla.org/en-US/docs/Glossary/bfcache) 37. [BiDi](https://developer.mozilla.org/en-US/docs/Glossary/BiDi) 38. [BigInt](https://developer.mozilla.org/en-US/docs/Glossary/BigInt) 39. [Binding](https://developer.mozilla.org/en-US/docs/Glossary/Binding) 40. [Bitwise flags](https://developer.mozilla.org/en-US/docs/Glossary/Bitwise_flags) 41. [Blink](https://developer.mozilla.org/en-US/docs/Glossary/Blink) 42. [blink element (<blink> tag)](https://developer.mozilla.org/en-US/docs/Glossary/blink_element) 43. [Block](https://developer.mozilla.org/en-US/docs/Glossary/Block) 1. [Block (CSS)](https://developer.mozilla.org/en-US/docs/Glossary/Block/CSS) 2. [Block (scripting)](https://developer.mozilla.org/en-US/docs/Glossary/Block/Scripting) 44. [Block cipher mode of operation](https://developer.mozilla.org/en-US/docs/Glossary/Block_cipher_mode_of_operation) 45. [Block-level content](https://developer.mozilla.org/en-US/docs/Glossary/Block-level_content) 46. [Boolean](https://developer.mozilla.org/en-US/docs/Glossary/Boolean) 1. [Boolean (JavaScript)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/JavaScript) 2. [Boolean attribute (ARIA)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/ARIA) 3. [Boolean attribute (HTML)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/HTML) 47. [Bounding box](https://developer.mozilla.org/en-US/docs/Glossary/Bounding_box) 48. [Breadcrumb](https://developer.mozilla.org/en-US/docs/Glossary/Breadcrumb) 49. [Brotli


id: unicode-glossary-mdn-20260505-0
file: data/developer.mozilla.org/en-US/docs/Glossary/Unicode-0.md
category: reference
title: Unicode - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/Unicode
date_saved: 2026-05-05T05:48:12.080098+00:00
instance: kb-cron
parent: unicode-glossary-mdn-20260505-0
summary:
* [Skip to main content](https://developer.mozilla.org/en-US/docs/Glossary/Unicode#content) * [Skip to search](https://developer.mozilla.org/en-US/docs/Glossary/Unicode#search) [ MDN ](https://developer.mozilla.org/en-US/) HTML [HTML: Markup language](https://developer.mozilla.org/en-US/docs/Web/HTML) HTML reference * [Elements](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements) * [Global attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes) * [Attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Attributes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference "See all HTML references") HTML guides * [Responsive images](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Responsive_images) * [HTML cheatsheet](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Cheatsheet) * [Date & time formats](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Date_and_time_formats) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides "See all HTML guides") Markup languages * [SVG](https://developer.mozilla.org/en-US/docs/Web/SVG) * [MathML](https://developer.mozilla.org/en-US/docs/Web/MathML) * [XML](https://developer.mozilla.org/en-US/docs/Web/XML) CSS [CSS: Styling language](https://developer.mozilla.org/en-US/docs/Web/CSS) CSS reference * [Properties](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties) * [Selectors](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors) * [At-rules](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/At-rules) * [Values](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference "See all CSS references") CSS guides * [Box model](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Box_model/Introduction) * [Animations](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Animations/Using) * [Flexbox](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Flexible_box_layout/Basic_concepts) * [Colors](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Colors/Applying_color) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides "See all CSS guides") Layout cookbook * [Column layouts](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Column_layouts) * [Centering an element](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Center_an_element) * [Card component](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Card) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook) JavaScriptJS [JavaScript: Scripting language](https://developer.mozilla.org/en-US/docs/Web/JavaScript) JS reference * [Standard built-in objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects) * [Expressions & operators](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators) * [Statements & declarations](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements) * [Functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference "See all JavaScript references") JS guides * [Control flow & error handing](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Control_flow_and_error_handling) * [Loops and iteration](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration) * [Working with objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_objects) * [Using classes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_classes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide "See all JavaScript guides") Web APIs [Web APIs: Programming interfaces](https://developer.mozilla.org/en-US/docs/Web/API) Web API reference * [File system API](https://developer.mozilla.org/en-US/docs/Web/API/File_System_API) * [Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) * [Geolocation API](https://developer.mozilla.org/en-US/docs/Web/API/Geolocation_API) * [HTML DOM API](https://developer.mozilla.org/en-US/docs/Web/API/HTML_DOM_API) * [Push API](https://developer.mozilla.org/en-US/docs/Web/API/Push_API) * [Service worker API](https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API) * [See all…](https://developer.mozilla.org/en-US/docs/Web/API


id: unicode-glossary-mdn-20260505-1
file: data/developer.mozilla.org/en-US/docs/Glossary/Unicode-1.md
category: reference
title: Unicode - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/Unicode
date_saved: 2026-05-05T05:48:12.080098+00:00
instance: kb-cron
parent: unicode-glossary-mdn-20260505-0
summary:
## Help improve MDN [Learn how to contribute](https://developer.mozilla.org/en-US/docs/MDN/Community/Getting_started) This page was last modified on Jul 11, 2025 by [MDN contributors](https://developer.mozilla.org/en-US/docs/Glossary/Unicode/contributors.txt). [View this page on GitHub](https://github.com/mdn/content/blob/main/files/en-us/glossary/unicode/index.md?plain=1 "Folder: en-us/glossary/unicode \(Opens in a new tab\)") • [Report a problem with this content](https://github.com/mdn/content/issues/new?template=page-report.yml&mdn-url=https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FUnicode&metadata=%3C%21--+Do+not+make+changes+below+this+line+--%3E%0A%3Cdetails%3E%0A%3Csummary%3EPage+report+details%3C%2Fsummary%3E%0A%0A*+Folder%3A+%60en-us%2Fglossary%2Funicode%60%0A*+MDN+URL%3A+https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FUnicode%0A*+GitHub+URL%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fblob%2Fmain%2Ffiles%2Fen-us%2Fglossary%2Funicode%2Findex.md%0A*+Last+commit%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fcommit%2F2547f622337d6cbf8c3794776b17ed377d6aad57%0A*+Document+last+modified%3A+2025-07-11T14%3A45%3A59.000Z%0A%0A%3C%2Fdetails%3E "This will take you to GitHub to file a new issue.") 1. [Glossary](https://developer.mozilla.org/en-US/docs/Glossary) 2. 1. [Abstraction](https://developer.mozilla.org/en-US/docs/Glossary/Abstraction) 2. [Accent](https://developer.mozilla.org/en-US/docs/Glossary/Accent) 3. [Accessibility](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility) 4. [Accessibility tree](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility_tree) 5. [Accessible description](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_description) 6. [Accessible name](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_name) 7. [Adobe Flash](https://developer.mozilla.org/en-US/docs/Glossary/Adobe_Flash) 8. [Advance measure](https://developer.mozilla.org/en-US/docs/Glossary/Advance_measure) 9. [Ajax](https://developer.mozilla.org/en-US/docs/Glossary/AJAX) 10. [Algorithm](https://developer.mozilla.org/en-US/docs/Glossary/Algorithm) 11. [Alignment container](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Container) 12. [Alignment subject](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Subject) 13. [Alpha (alpha channel)](https://developer.mozilla.org/en-US/docs/Glossary/Alpha) 14. [ALPN](https://developer.mozilla.org/en-US/docs/Glossary/ALPN) 15. [API](https://developer.mozilla.org/en-US/docs/Glossary/API) 16. [Apple Safari](https://developer.mozilla.org/en-US/docs/Glossary/Apple_Safari) 17. [Application context](https://developer.mozilla.org/en-US/docs/Glossary/Application_context) 18. [Argument](https://developer.mozilla.org/en-US/docs/Glossary/Argument) 19. [ARIA](https://developer.mozilla.org/en-US/docs/Glossary/ARIA) 20. [ARPA](https://developer.mozilla.org/en-US/docs/Glossary/ARPA) 21. [ARPANET](https://developer.mozilla.org/en-US/docs/Glossary/Arpanet) 22. [Array](https://developer.mozilla.org/en-US/docs/Glossary/Array) 23. [ASCII](https://developer.mozilla.org/en-US/docs/Glossary/ASCII) 24. [Aspect ratio](https://developer.mozilla.org/en-US/docs/Glossary/Aspect_ratio) 25. [Asynchronous](https://developer.mozilla.org/en-US/docs/Glossary/Asynchronous) 26. [ATAG](https://developer.mozilla.org/en-US/docs/Glossary/ATAG) 27. [Attribute](https://developer.mozilla.org/en-US/docs/Glossary/Attribute) 28. [Authentication](https://developer.mozilla.org/en-US/docs/Glossary/Authentication) 29. [Authenticator](https://developer.mozilla.org/en-US/docs/Glossary/Authenticator) 30. [Bandwidth](https://developer.mozilla.org/en-US/docs/Glossary/Bandwidth) 31. [Base64](https://developer.mozilla.org/en-US/docs/Glossary/Base64) 32. [Baseline](https://developer.mozilla.org/en-US/docs/Glossary/Baseline) 1. [Baseline (compatibility)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Compatibility) 2. [Baseline (typography)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Typography) 33. [BCP 47 language tag](https://developer.mozilla.org/en-US/docs/Glossary/BCP_47_language_tag) 34. [Beacon](https://developer.mozilla.org/en-US/docs/Glossary/Beacon) 35. [Bézier curve](https://developer.mozilla.org/en-US/docs/Glossary/Bezier_curve) 36. [bfcache](https://developer.mozilla.org/en-US/docs/Glossary/bfcache) 37. [BiDi](https://developer.mozilla.org/en-US/docs/Glossary/BiDi) 38. [BigInt](https://developer.mozilla.org/en-US/docs/Glossary/BigInt) 39. [Binding](https://developer.mozilla.org/en-US/docs/Glossary/Binding) 40. [Bitwise flags](https://developer.mozilla.org/en-US/docs/Glossary/Bitwise_flags) 41. [Blink](https://developer.mozilla.org/en-US/docs/Glossary/Blink) 42. [blink element (<blink> tag)](https://developer.mozilla.org/en-US/docs/Glossary/blink_element) 43. [Block](https://developer.mozilla.org/en-US/docs/Glossary/Block) 1. [Block (CSS)](https://developer.mozilla.org/en-US/docs/Glossary/Block/CSS) 2. [Block (scripting)](https://developer.mozilla.org/en-US/docs/Glossary/Block/Scripting) 44. [Block cipher mode of operation](https://developer.mozilla.org/en-US/docs/Glossary/Block_cipher_mode_of_operation) 45. [Block-level content](https://developer.mozilla.org/en-US/docs/Glossary/Block-level_content) 46. [Boolean](https://developer.mozilla.org/en-US/docs/Glossary/Boolean) 1. [Boolean (JavaScript)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/JavaScript) 2. [Boolean attribute (ARIA)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/ARIA) 3. [Boolean attribute (HTML)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/HTML) 47. [Bounding box](https://developer.mozilla.org/en-US/docs/Glossary/Bounding_box) 48. [Breadcrumb](https://developer.mozilla.org/en-US/docs/Glossary/Breadcrumb) 49. [Brotli


id: unix-time-glossary-mdn-20260505-0
file: data/developer.mozilla.org/en-US/docs/Glossary/Unix_time-0.md
category: reference
title: Unix time - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/Unix_time
date_saved: 2026-05-05T05:48:14.573236+00:00
instance: kb-cron
parent: unix-time-glossary-mdn-20260505-0
summary:
* [Skip to main content](https://developer.mozilla.org/en-US/docs/Glossary/Unix_time#content) * [Skip to search](https://developer.mozilla.org/en-US/docs/Glossary/Unix_time#search) [ MDN ](https://developer.mozilla.org/en-US/) HTML [HTML: Markup language](https://developer.mozilla.org/en-US/docs/Web/HTML) HTML reference * [Elements](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements) * [Global attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes) * [Attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Attributes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference "See all HTML references") HTML guides * [Responsive images](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Responsive_images) * [HTML cheatsheet](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Cheatsheet) * [Date & time formats](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Date_and_time_formats) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides "See all HTML guides") Markup languages * [SVG](https://developer.mozilla.org/en-US/docs/Web/SVG) * [MathML](https://developer.mozilla.org/en-US/docs/Web/MathML) * [XML](https://developer.mozilla.org/en-US/docs/Web/XML) CSS [CSS: Styling language](https://developer.mozilla.org/en-US/docs/Web/CSS) CSS reference * [Properties](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties) * [Selectors](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors) * [At-rules](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/At-rules) * [Values](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference "See all CSS references") CSS guides * [Box model](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Box_model/Introduction) * [Animations](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Animations/Using) * [Flexbox](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Flexible_box_layout/Basic_concepts) * [Colors](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Colors/Applying_color) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides "See all CSS guides") Layout cookbook * [Column layouts](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Column_layouts) * [Centering an element](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Center_an_element) * [Card component](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Card) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook) JavaScriptJS [JavaScript: Scripting language](https://developer.mozilla.org/en-US/docs/Web/JavaScript) JS reference * [Standard built-in objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects) * [Expressions & operators](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators) * [Statements & declarations](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements) * [Functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference "See all JavaScript references") JS guides * [Control flow & error handing](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Control_flow_and_error_handling) * [Loops and iteration](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration) * [Working with objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_objects) * [Using classes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_classes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide "See all JavaScript guides") Web APIs [Web APIs: Programming interfaces](https://developer.mozilla.org/en-US/docs/Web/API) Web API reference * [File system API](https://developer.mozilla.org/en-US/docs/Web/API/File_System_API) * [Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) * [Geolocation API](https://developer.mozilla.org/en-US/docs/Web/API/Geolocation_API) * [HTML DOM API](https://developer.mozilla.org/en-US/docs/Web/API/HTML_DOM_API) * [Push API](https://developer.mozilla.org/en-US/docs/Web/API/Push_API) * [Service worker API](https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API) * [See all…](https://developer.mozilla.org/en-US/docs/Web/API


id: unix-time-glossary-mdn-20260505-1
file: data/developer.mozilla.org/en-US/docs/Glossary/Unix_time-1.md
category: reference
title: Unix time - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/Unix_time
date_saved: 2026-05-05T05:48:14.573236+00:00
instance: kb-cron
parent: unix-time-glossary-mdn-20260505-0
summary:
## Help improve MDN [Learn how to contribute](https://developer.mozilla.org/en-US/docs/MDN/Community/Getting_started) This page was last modified on Jul 11, 2025 by [MDN contributors](https://developer.mozilla.org/en-US/docs/Glossary/Unix_time/contributors.txt). [View this page on GitHub](https://github.com/mdn/content/blob/main/files/en-us/glossary/unix_time/index.md?plain=1 "Folder: en-us/glossary/unix_time \(Opens in a new tab\)") • [Report a problem with this content](https://github.com/mdn/content/issues/new?template=page-report.yml&mdn-url=https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FUnix_time&metadata=%3C%21--+Do+not+make+changes+below+this+line+--%3E%0A%3Cdetails%3E%0A%3Csummary%3EPage+report+details%3C%2Fsummary%3E%0A%0A*+Folder%3A+%60en-us%2Fglossary%2Funix_time%60%0A*+MDN+URL%3A+https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FUnix_time%0A*+GitHub+URL%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fblob%2Fmain%2Ffiles%2Fen-us%2Fglossary%2Funix_time%2Findex.md%0A*+Last+commit%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fcommit%2F2547f622337d6cbf8c3794776b17ed377d6aad57%0A*+Document+last+modified%3A+2025-07-11T14%3A45%3A59.000Z%0A%0A%3C%2Fdetails%3E "This will take you to GitHub to file a new issue.") 1. [Glossary](https://developer.mozilla.org/en-US/docs/Glossary) 2. 1. [Abstraction](https://developer.mozilla.org/en-US/docs/Glossary/Abstraction) 2. [Accent](https://developer.mozilla.org/en-US/docs/Glossary/Accent) 3. [Accessibility](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility) 4. [Accessibility tree](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility_tree) 5. [Accessible description](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_description) 6. [Accessible name](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_name) 7. [Adobe Flash](https://developer.mozilla.org/en-US/docs/Glossary/Adobe_Flash) 8. [Advance measure](https://developer.mozilla.org/en-US/docs/Glossary/Advance_measure) 9. [Ajax](https://developer.mozilla.org/en-US/docs/Glossary/AJAX) 10. [Algorithm](https://developer.mozilla.org/en-US/docs/Glossary/Algorithm) 11. [Alignment container](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Container) 12. [Alignment subject](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Subject) 13. [Alpha (alpha channel)](https://developer.mozilla.org/en-US/docs/Glossary/Alpha) 14. [ALPN](https://developer.mozilla.org/en-US/docs/Glossary/ALPN) 15. [API](https://developer.mozilla.org/en-US/docs/Glossary/API) 16. [Apple Safari](https://developer.mozilla.org/en-US/docs/Glossary/Apple_Safari) 17. [Application context](https://developer.mozilla.org/en-US/docs/Glossary/Application_context) 18. [Argument](https://developer.mozilla.org/en-US/docs/Glossary/Argument) 19. [ARIA](https://developer.mozilla.org/en-US/docs/Glossary/ARIA) 20. [ARPA](https://developer.mozilla.org/en-US/docs/Glossary/ARPA) 21. [ARPANET](https://developer.mozilla.org/en-US/docs/Glossary/Arpanet) 22. [Array](https://developer.mozilla.org/en-US/docs/Glossary/Array) 23. [ASCII](https://developer.mozilla.org/en-US/docs/Glossary/ASCII) 24. [Aspect ratio](https://developer.mozilla.org/en-US/docs/Glossary/Aspect_ratio) 25. [Asynchronous](https://developer.mozilla.org/en-US/docs/Glossary/Asynchronous) 26. [ATAG](https://developer.mozilla.org/en-US/docs/Glossary/ATAG) 27. [Attribute](https://developer.mozilla.org/en-US/docs/Glossary/Attribute) 28. [Authentication](https://developer.mozilla.org/en-US/docs/Glossary/Authentication) 29. [Authenticator](https://developer.mozilla.org/en-US/docs/Glossary/Authenticator) 30. [Bandwidth](https://developer.mozilla.org/en-US/docs/Glossary/Bandwidth) 31. [Base64](https://developer.mozilla.org/en-US/docs/Glossary/Base64) 32. [Baseline](https://developer.mozilla.org/en-US/docs/Glossary/Baseline) 1. [Baseline (compatibility)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Compatibility) 2. [Baseline (typography)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Typography) 33. [BCP 47 language tag](https://developer.mozilla.org/en-US/docs/Glossary/BCP_47_language_tag) 34. [Beacon](https://developer.mozilla.org/en-US/docs/Glossary/Beacon) 35. [Bézier curve](https://developer.mozilla.org/en-US/docs/Glossary/Bezier_curve) 36. [bfcache](https://developer.mozilla.org/en-US/docs/Glossary/bfcache) 37. [BiDi](https://developer.mozilla.org/en-US/docs/Glossary/BiDi) 38. [BigInt](https://developer.mozilla.org/en-US/docs/Glossary/BigInt) 39. [Binding](https://developer.mozilla.org/en-US/docs/Glossary/Binding) 40. [Bitwise flags](https://developer.mozilla.org/en-US/docs/Glossary/Bitwise_flags) 41. [Blink](https://developer.mozilla.org/en-US/docs/Glossary/Blink) 42. [blink element (<blink> tag)](https://developer.mozilla.org/en-US/docs/Glossary/blink_element) 43. [Block](https://developer.mozilla.org/en-US/docs/Glossary/Block) 1. [Block (CSS)](https://developer.mozilla.org/en-US/docs/Glossary/Block/CSS) 2. [Block (scripting)](https://developer.mozilla.org/en-US/docs/Glossary/Block/Scripting) 44. [Block cipher mode of operation](https://developer.mozilla.org/en-US/docs/Glossary/Block_cipher_mode_of_operation) 45. [Block-level content](https://developer.mozilla.org/en-US/docs/Glossary/Block-level_content) 46. [Boolean](https://developer.mozilla.org/en-US/docs/Glossary/Boolean) 1. [Boolean (JavaScript)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/JavaScript) 2. [Boolean attribute (ARIA)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/ARIA) 3. [Boolean attribute (HTML)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/HTML) 47. [Bounding box](https://developer.mozilla.org/en-US/docs/Glossary/Bounding_box) 48. [Breadcrumb](https://developer.mozilla.org/en-US/docs/Glossary/Breadcrumb) 49. [Brotli


id: usenet-glossary-mdn-20260505-0
file: data/developer.mozilla.org/en-US/docs/Glossary/Usenet-0.md
category: reference
title: Usenet - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/Usenet
date_saved: 2026-05-05T05:48:16.912602+00:00
instance: kb-cron
parent: usenet-glossary-mdn-20260505-0
summary:
* [Skip to main content](https://developer.mozilla.org/en-US/docs/Glossary/Usenet#content) * [Skip to search](https://developer.mozilla.org/en-US/docs/Glossary/Usenet#search) [ MDN ](https://developer.mozilla.org/en-US/) HTML [HTML: Markup language](https://developer.mozilla.org/en-US/docs/Web/HTML) HTML reference * [Elements](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements) * [Global attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes) * [Attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Attributes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference "See all HTML references") HTML guides * [Responsive images](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Responsive_images) * [HTML cheatsheet](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Cheatsheet) * [Date & time formats](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Date_and_time_formats) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides "See all HTML guides") Markup languages * [SVG](https://developer.mozilla.org/en-US/docs/Web/SVG) * [MathML](https://developer.mozilla.org/en-US/docs/Web/MathML) * [XML](https://developer.mozilla.org/en-US/docs/Web/XML) CSS [CSS: Styling language](https://developer.mozilla.org/en-US/docs/Web/CSS) CSS reference * [Properties](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties) * [Selectors](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors) * [At-rules](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/At-rules) * [Values](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference "See all CSS references") CSS guides * [Box model](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Box_model/Introduction) * [Animations](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Animations/Using) * [Flexbox](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Flexible_box_layout/Basic_concepts) * [Colors](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Colors/Applying_color) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides "See all CSS guides") Layout cookbook * [Column layouts](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Column_layouts) * [Centering an element](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Center_an_element) * [Card component](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Card) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook) JavaScriptJS [JavaScript: Scripting language](https://developer.mozilla.org/en-US/docs/Web/JavaScript) JS reference * [Standard built-in objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects) * [Expressions & operators](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators) * [Statements & declarations](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements) * [Functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference "See all JavaScript references") JS guides * [Control flow & error handing](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Control_flow_and_error_handling) * [Loops and iteration](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration) * [Working with objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_objects) * [Using classes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_classes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide "See all JavaScript guides") Web APIs [Web APIs: Programming interfaces](https://developer.mozilla.org/en-US/docs/Web/API) Web API reference * [File system API](https://developer.mozilla.org/en-US/docs/Web/API/File_System_API) * [Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) * [Geolocation API](https://developer.mozilla.org/en-US/docs/Web/API/Geolocation_API) * [HTML DOM API](https://developer.mozilla.org/en-US/docs/Web/API/HTML_DOM_API) * [Push API](https://developer.mozilla.org/en-US/docs/Web/API/Push_API) * [Service worker API](https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API) * [See all…](https://developer.mozilla.org/en-US/docs/Web/API


id: usenet-glossary-mdn-20260505-1
file: data/developer.mozilla.org/en-US/docs/Glossary/Usenet-1.md
category: reference
title: Usenet - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/Usenet
date_saved: 2026-05-05T05:48:16.912602+00:00
instance: kb-cron
parent: usenet-glossary-mdn-20260505-0
summary:
## Help improve MDN [Learn how to contribute](https://developer.mozilla.org/en-US/docs/MDN/Community/Getting_started) This page was last modified on Jul 11, 2025 by [MDN contributors](https://developer.mozilla.org/en-US/docs/Glossary/Usenet/contributors.txt). [View this page on GitHub](https://github.com/mdn/content/blob/main/files/en-us/glossary/usenet/index.md?plain=1 "Folder: en-us/glossary/usenet \(Opens in a new tab\)") • [Report a problem with this content](https://github.com/mdn/content/issues/new?template=page-report.yml&mdn-url=https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FUsenet&metadata=%3C%21--+Do+not+make+changes+below+this+line+--%3E%0A%3Cdetails%3E%0A%3Csummary%3EPage+report+details%3C%2Fsummary%3E%0A%0A*+Folder%3A+%60en-us%2Fglossary%2Fusenet%60%0A*+MDN+URL%3A+https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FUsenet%0A*+GitHub+URL%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fblob%2Fmain%2Ffiles%2Fen-us%2Fglossary%2Fusenet%2Findex.md%0A*+Last+commit%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fcommit%2F2547f622337d6cbf8c3794776b17ed377d6aad57%0A*+Document+last+modified%3A+2025-07-11T14%3A45%3A59.000Z%0A%0A%3C%2Fdetails%3E "This will take you to GitHub to file a new issue.") 1. [Glossary](https://developer.mozilla.org/en-US/docs/Glossary) 2. 1. [Abstraction](https://developer.mozilla.org/en-US/docs/Glossary/Abstraction) 2. [Accent](https://developer.mozilla.org/en-US/docs/Glossary/Accent) 3. [Accessibility](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility) 4. [Accessibility tree](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility_tree) 5. [Accessible description](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_description) 6. [Accessible name](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_name) 7. [Adobe Flash](https://developer.mozilla.org/en-US/docs/Glossary/Adobe_Flash) 8. [Advance measure](https://developer.mozilla.org/en-US/docs/Glossary/Advance_measure) 9. [Ajax](https://developer.mozilla.org/en-US/docs/Glossary/AJAX) 10. [Algorithm](https://developer.mozilla.org/en-US/docs/Glossary/Algorithm) 11. [Alignment container](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Container) 12. [Alignment subject](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Subject) 13. [Alpha (alpha channel)](https://developer.mozilla.org/en-US/docs/Glossary/Alpha) 14. [ALPN](https://developer.mozilla.org/en-US/docs/Glossary/ALPN) 15. [API](https://developer.mozilla.org/en-US/docs/Glossary/API) 16. [Apple Safari](https://developer.mozilla.org/en-US/docs/Glossary/Apple_Safari) 17. [Application context](https://developer.mozilla.org/en-US/docs/Glossary/Application_context) 18. [Argument](https://developer.mozilla.org/en-US/docs/Glossary/Argument) 19. [ARIA](https://developer.mozilla.org/en-US/docs/Glossary/ARIA) 20. [ARPA](https://developer.mozilla.org/en-US/docs/Glossary/ARPA) 21. [ARPANET](https://developer.mozilla.org/en-US/docs/Glossary/Arpanet) 22. [Array](https://developer.mozilla.org/en-US/docs/Glossary/Array) 23. [ASCII](https://developer.mozilla.org/en-US/docs/Glossary/ASCII) 24. [Aspect ratio](https://developer.mozilla.org/en-US/docs/Glossary/Aspect_ratio) 25. [Asynchronous](https://developer.mozilla.org/en-US/docs/Glossary/Asynchronous) 26. [ATAG](https://developer.mozilla.org/en-US/docs/Glossary/ATAG) 27. [Attribute](https://developer.mozilla.org/en-US/docs/Glossary/Attribute) 28. [Authentication](https://developer.mozilla.org/en-US/docs/Glossary/Authentication) 29. [Authenticator](https://developer.mozilla.org/en-US/docs/Glossary/Authenticator) 30. [Bandwidth](https://developer.mozilla.org/en-US/docs/Glossary/Bandwidth) 31. [Base64](https://developer.mozilla.org/en-US/docs/Glossary/Base64) 32. [Baseline](https://developer.mozilla.org/en-US/docs/Glossary/Baseline) 1. [Baseline (compatibility)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Compatibility) 2. [Baseline (typography)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Typography) 33. [BCP 47 language tag](https://developer.mozilla.org/en-US/docs/Glossary/BCP_47_language_tag) 34. [Beacon](https://developer.mozilla.org/en-US/docs/Glossary/Beacon) 35. [Bézier curve](https://developer.mozilla.org/en-US/docs/Glossary/Bezier_curve) 36. [bfcache](https://developer.mozilla.org/en-US/docs/Glossary/bfcache) 37. [BiDi](https://developer.mozilla.org/en-US/docs/Glossary/BiDi) 38. [BigInt](https://developer.mozilla.org/en-US/docs/Glossary/BigInt) 39. [Binding](https://developer.mozilla.org/en-US/docs/Glossary/Binding) 40. [Bitwise flags](https://developer.mozilla.org/en-US/docs/Glossary/Bitwise_flags) 41. [Blink](https://developer.mozilla.org/en-US/docs/Glossary/Blink) 42. [blink element (<blink> tag)](https://developer.mozilla.org/en-US/docs/Glossary/blink_element) 43. [Block](https://developer.mozilla.org/en-US/docs/Glossary/Block) 1. [Block (CSS)](https://developer.mozilla.org/en-US/docs/Glossary/Block/CSS) 2. [Block (scripting)](https://developer.mozilla.org/en-US/docs/Glossary/Block/Scripting) 44. [Block cipher mode of operation](https://developer.mozilla.org/en-US/docs/Glossary/Block_cipher_mode_of_operation) 45. [Block-level content](https://developer.mozilla.org/en-US/docs/Glossary/Block-level_content) 46. [Boolean](https://developer.mozilla.org/en-US/docs/Glossary/Boolean) 1. [Boolean (JavaScript)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/JavaScript) 2. [Boolean attribute (ARIA)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/ARIA) 3. [Boolean attribute (HTML)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/HTML) 47. [Bounding box](https://developer.mozilla.org/en-US/docs/Glossary/Bounding_box) 48. [Breadcrumb](https://developer.mozilla.org/en-US/docs/Glossary/Breadcrumb) 49. [Brotli


id: user-agent-glossary-mdn-20260505-0
file: data/developer.mozilla.org/en-US/docs/Glossary/User_agent-0.md
category: reference
title: User agent - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/User_agent
date_saved: 2026-05-05T05:48:19.289342+00:00
instance: kb-cron
parent: user-agent-glossary-mdn-20260505-0
summary:
* [Skip to main content](https://developer.mozilla.org/en-US/docs/Glossary/User_agent#content) * [Skip to search](https://developer.mozilla.org/en-US/docs/Glossary/User_agent#search) [ MDN ](https://developer.mozilla.org/en-US/) HTML [HTML: Markup language](https://developer.mozilla.org/en-US/docs/Web/HTML) HTML reference * [Elements](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements) * [Global attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes) * [Attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Attributes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference "See all HTML references") HTML guides * [Responsive images](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Responsive_images) * [HTML cheatsheet](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Cheatsheet) * [Date & time formats](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Date_and_time_formats) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides "See all HTML guides") Markup languages * [SVG](https://developer.mozilla.org/en-US/docs/Web/SVG) * [MathML](https://developer.mozilla.org/en-US/docs/Web/MathML) * [XML](https://developer.mozilla.org/en-US/docs/Web/XML) CSS [CSS: Styling language](https://developer.mozilla.org/en-US/docs/Web/CSS) CSS reference * [Properties](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties) * [Selectors](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors) * [At-rules](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/At-rules) * [Values](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference "See all CSS references") CSS guides * [Box model](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Box_model/Introduction) * [Animations](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Animations/Using) * [Flexbox](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Flexible_box_layout/Basic_concepts) * [Colors](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Colors/Applying_color) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides "See all CSS guides") Layout cookbook * [Column layouts](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Column_layouts) * [Centering an element](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Center_an_element) * [Card component](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Card) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook) JavaScriptJS [JavaScript: Scripting language](https://developer.mozilla.org/en-US/docs/Web/JavaScript) JS reference * [Standard built-in objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects) * [Expressions & operators](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators) * [Statements & declarations](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements) * [Functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference "See all JavaScript references") JS guides * [Control flow & error handing](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Control_flow_and_error_handling) * [Loops and iteration](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration) * [Working with objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_objects) * [Using classes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_classes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide "See all JavaScript guides") Web APIs [Web APIs: Programming interfaces](https://developer.mozilla.org/en-US/docs/Web/API) Web API reference * [File system API](https://developer.mozilla.org/en-US/docs/Web/API/File_System_API) * [Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) * [Geolocation API](https://developer.mozilla.org/en-US/docs/Web/API/Geolocation_API) * [HTML DOM API](https://developer.mozilla.org/en-US/docs/Web/API/HTML_DOM_API) * [Push API](https://developer.mozilla.org/en-US/docs/Web/API/Push_API) * [Service worker API](https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API) * [See all…](https://developer.mozilla.org/en-US/docs/Web/API


id: user-agent-glossary-mdn-20260505-1
file: data/developer.mozilla.org/en-US/docs/Glossary/User_agent-1.md
category: reference
title: User agent - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/User_agent
date_saved: 2026-05-05T05:48:19.289342+00:00
instance: kb-cron
parent: user-agent-glossary-mdn-20260505-0
summary:
## Help improve MDN [Learn how to contribute](https://developer.mozilla.org/en-US/docs/MDN/Community/Getting_started) This page was last modified on Jul 11, 2025 by [MDN contributors](https://developer.mozilla.org/en-US/docs/Glossary/User_agent/contributors.txt). [View this page on GitHub](https://github.com/mdn/content/blob/main/files/en-us/glossary/user_agent/index.md?plain=1 "Folder: en-us/glossary/user_agent \(Opens in a new tab\)") • [Report a problem with this content](https://github.com/mdn/content/issues/new?template=page-report.yml&mdn-url=https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FUser_agent&metadata=%3C%21--+Do+not+make+changes+below+this+line+--%3E%0A%3Cdetails%3E%0A%3Csummary%3EPage+report+details%3C%2Fsummary%3E%0A%0A*+Folder%3A+%60en-us%2Fglossary%2Fuser_agent%60%0A*+MDN+URL%3A+https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FUser_agent%0A*+GitHub+URL%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fblob%2Fmain%2Ffiles%2Fen-us%2Fglossary%2Fuser_agent%2Findex.md%0A*+Last+commit%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fcommit%2F2547f622337d6cbf8c3794776b17ed377d6aad57%0A*+Document+last+modified%3A+2025-07-11T14%3A45%3A59.000Z%0A%0A%3C%2Fdetails%3E "This will take you to GitHub to file a new issue.") 1. [Glossary](https://developer.mozilla.org/en-US/docs/Glossary) 2. 1. [Abstraction](https://developer.mozilla.org/en-US/docs/Glossary/Abstraction) 2. [Accent](https://developer.mozilla.org/en-US/docs/Glossary/Accent) 3. [Accessibility](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility) 4. [Accessibility tree](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility_tree) 5. [Accessible description](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_description) 6. [Accessible name](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_name) 7. [Adobe Flash](https://developer.mozilla.org/en-US/docs/Glossary/Adobe_Flash) 8. [Advance measure](https://developer.mozilla.org/en-US/docs/Glossary/Advance_measure) 9. [Ajax](https://developer.mozilla.org/en-US/docs/Glossary/AJAX) 10. [Algorithm](https://developer.mozilla.org/en-US/docs/Glossary/Algorithm) 11. [Alignment container](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Container) 12. [Alignment subject](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Subject) 13. [Alpha (alpha channel)](https://developer.mozilla.org/en-US/docs/Glossary/Alpha) 14. [ALPN](https://developer.mozilla.org/en-US/docs/Glossary/ALPN) 15. [API](https://developer.mozilla.org/en-US/docs/Glossary/API) 16. [Apple Safari](https://developer.mozilla.org/en-US/docs/Glossary/Apple_Safari) 17. [Application context](https://developer.mozilla.org/en-US/docs/Glossary/Application_context) 18. [Argument](https://developer.mozilla.org/en-US/docs/Glossary/Argument) 19. [ARIA](https://developer.mozilla.org/en-US/docs/Glossary/ARIA) 20. [ARPA](https://developer.mozilla.org/en-US/docs/Glossary/ARPA) 21. [ARPANET](https://developer.mozilla.org/en-US/docs/Glossary/Arpanet) 22. [Array](https://developer.mozilla.org/en-US/docs/Glossary/Array) 23. [ASCII](https://developer.mozilla.org/en-US/docs/Glossary/ASCII) 24. [Aspect ratio](https://developer.mozilla.org/en-US/docs/Glossary/Aspect_ratio) 25. [Asynchronous](https://developer.mozilla.org/en-US/docs/Glossary/Asynchronous) 26. [ATAG](https://developer.mozilla.org/en-US/docs/Glossary/ATAG) 27. [Attribute](https://developer.mozilla.org/en-US/docs/Glossary/Attribute) 28. [Authentication](https://developer.mozilla.org/en-US/docs/Glossary/Authentication) 29. [Authenticator](https://developer.mozilla.org/en-US/docs/Glossary/Authenticator) 30. [Bandwidth](https://developer.mozilla.org/en-US/docs/Glossary/Bandwidth) 31. [Base64](https://developer.mozilla.org/en-US/docs/Glossary/Base64) 32. [Baseline](https://developer.mozilla.org/en-US/docs/Glossary/Baseline) 1. [Baseline (compatibility)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Compatibility) 2. [Baseline (typography)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Typography) 33. [BCP 47 language tag](https://developer.mozilla.org/en-US/docs/Glossary/BCP_47_language_tag) 34. [Beacon](https://developer.mozilla.org/en-US/docs/Glossary/Beacon) 35. [Bézier curve](https://developer.mozilla.org/en-US/docs/Glossary/Bezier_curve) 36. [bfcache](https://developer.mozilla.org/en-US/docs/Glossary/bfcache) 37. [BiDi](https://developer.mozilla.org/en-US/docs/Glossary/BiDi) 38. [BigInt](https://developer.mozilla.org/en-US/docs/Glossary/BigInt) 39. [Binding](https://developer.mozilla.org/en-US/docs/Glossary/Binding) 40. [Bitwise flags](https://developer.mozilla.org/en-US/docs/Glossary/Bitwise_flags) 41. [Blink](https://developer.mozilla.org/en-US/docs/Glossary/Blink) 42. [blink element (<blink> tag)](https://developer.mozilla.org/en-US/docs/Glossary/blink_element) 43. [Block](https://developer.mozilla.org/en-US/docs/Glossary/Block) 1. [Block (CSS)](https://developer.mozilla.org/en-US/docs/Glossary/Block/CSS) 2. [Block (scripting)](https://developer.mozilla.org/en-US/docs/Glossary/Block/Scripting) 44. [Block cipher mode of operation](https://developer.mozilla.org/en-US/docs/Glossary/Block_cipher_mode_of_operation) 45. [Block-level content](https://developer.mozilla.org/en-US/docs/Glossary/Block-level_content) 46. [Boolean](https://developer.mozilla.org/en-US/docs/Glossary/Boolean) 1. [Boolean (JavaScript)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/JavaScript) 2. [Boolean attribute (ARIA)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/ARIA) 3. [Boolean attribute (HTML)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/HTML) 47. [Bounding box](https://developer.mozilla.org/en-US/docs/Glossary/Bounding_box) 48. [Breadcrumb](https://developer.mozilla.org/en-US/docs/Glossary/Breadcrumb) 49. [Brotli


id: validator-glossary-mdn-20260505-0
file: data/developer.mozilla.org/en-US/docs/Glossary/Validator-0.md
category: reference
title: Validator - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/Validator
date_saved: 2026-05-05T05:48:21.712046+00:00
instance: kb-cron
parent: validator-glossary-mdn-20260505-0
summary:
* [Skip to main content](https://developer.mozilla.org/en-US/docs/Glossary/Validator#content) * [Skip to search](https://developer.mozilla.org/en-US/docs/Glossary/Validator#search) [ MDN ](https://developer.mozilla.org/en-US/) HTML [HTML: Markup language](https://developer.mozilla.org/en-US/docs/Web/HTML) HTML reference * [Elements](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements) * [Global attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes) * [Attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Attributes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference "See all HTML references") HTML guides * [Responsive images](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Responsive_images) * [HTML cheatsheet](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Cheatsheet) * [Date & time formats](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Date_and_time_formats) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides "See all HTML guides") Markup languages * [SVG](https://developer.mozilla.org/en-US/docs/Web/SVG) * [MathML](https://developer.mozilla.org/en-US/docs/Web/MathML) * [XML](https://developer.mozilla.org/en-US/docs/Web/XML) CSS [CSS: Styling language](https://developer.mozilla.org/en-US/docs/Web/CSS) CSS reference * [Properties](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties) * [Selectors](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors) * [At-rules](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/At-rules) * [Values](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference "See all CSS references") CSS guides * [Box model](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Box_model/Introduction) * [Animations](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Animations/Using) * [Flexbox](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Flexible_box_layout/Basic_concepts) * [Colors](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Colors/Applying_color) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides "See all CSS guides") Layout cookbook * [Column layouts](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Column_layouts) * [Centering an element](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Center_an_element) * [Card component](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Card) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook) JavaScriptJS [JavaScript: Scripting language](https://developer.mozilla.org/en-US/docs/Web/JavaScript) JS reference * [Standard built-in objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects) * [Expressions & operators](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators) * [Statements & declarations](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements) * [Functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference "See all JavaScript references") JS guides * [Control flow & error handing](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Control_flow_and_error_handling) * [Loops and iteration](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration) * [Working with objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_objects) * [Using classes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_classes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide "See all JavaScript guides") Web APIs [Web APIs: Programming interfaces](https://developer.mozilla.org/en-US/docs/Web/API) Web API reference * [File system API](https://developer.mozilla.org/en-US/docs/Web/API/File_System_API) * [Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) * [Geolocation API](https://developer.mozilla.org/en-US/docs/Web/API/Geolocation_API) * [HTML DOM API](https://developer.mozilla.org/en-US/docs/Web/API/HTML_DOM_API) * [Push API](https://developer.mozilla.org/en-US/docs/Web/API/Push_API) * [Service worker API](https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API) * [See all…](https://developer.mozilla.org/en-US/docs/Web/API


id: validator-glossary-mdn-20260505-1
file: data/developer.mozilla.org/en-US/docs/Glossary/Validator-1.md
category: reference
title: Validator - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/Validator
date_saved: 2026-05-05T05:48:21.712046+00:00
instance: kb-cron
parent: validator-glossary-mdn-20260505-0
summary:
## Help improve MDN [Learn how to contribute](https://developer.mozilla.org/en-US/docs/MDN/Community/Getting_started) This page was last modified on Jul 11, 2025 by [MDN contributors](https://developer.mozilla.org/en-US/docs/Glossary/Validator/contributors.txt). [View this page on GitHub](https://github.com/mdn/content/blob/main/files/en-us/glossary/validator/index.md?plain=1 "Folder: en-us/glossary/validator \(Opens in a new tab\)") • [Report a problem with this content](https://github.com/mdn/content/issues/new?template=page-report.yml&mdn-url=https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FValidator&metadata=%3C%21--+Do+not+make+changes+below+this+line+--%3E%0A%3Cdetails%3E%0A%3Csummary%3EPage+report+details%3C%2Fsummary%3E%0A%0A*+Folder%3A+%60en-us%2Fglossary%2Fvalidator%60%0A*+MDN+URL%3A+https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FValidator%0A*+GitHub+URL%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fblob%2Fmain%2Ffiles%2Fen-us%2Fglossary%2Fvalidator%2Findex.md%0A*+Last+commit%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fcommit%2F2547f622337d6cbf8c3794776b17ed377d6aad57%0A*+Document+last+modified%3A+2025-07-11T14%3A45%3A59.000Z%0A%0A%3C%2Fdetails%3E "This will take you to GitHub to file a new issue.") 1. [Glossary](https://developer.mozilla.org/en-US/docs/Glossary) 2. 1. [Abstraction](https://developer.mozilla.org/en-US/docs/Glossary/Abstraction) 2. [Accent](https://developer.mozilla.org/en-US/docs/Glossary/Accent) 3. [Accessibility](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility) 4. [Accessibility tree](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility_tree) 5. [Accessible description](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_description) 6. [Accessible name](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_name) 7. [Adobe Flash](https://developer.mozilla.org/en-US/docs/Glossary/Adobe_Flash) 8. [Advance measure](https://developer.mozilla.org/en-US/docs/Glossary/Advance_measure) 9. [Ajax](https://developer.mozilla.org/en-US/docs/Glossary/AJAX) 10. [Algorithm](https://developer.mozilla.org/en-US/docs/Glossary/Algorithm) 11. [Alignment container](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Container) 12. [Alignment subject](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Subject) 13. [Alpha (alpha channel)](https://developer.mozilla.org/en-US/docs/Glossary/Alpha) 14. [ALPN](https://developer.mozilla.org/en-US/docs/Glossary/ALPN) 15. [API](https://developer.mozilla.org/en-US/docs/Glossary/API) 16. [Apple Safari](https://developer.mozilla.org/en-US/docs/Glossary/Apple_Safari) 17. [Application context](https://developer.mozilla.org/en-US/docs/Glossary/Application_context) 18. [Argument](https://developer.mozilla.org/en-US/docs/Glossary/Argument) 19. [ARIA](https://developer.mozilla.org/en-US/docs/Glossary/ARIA) 20. [ARPA](https://developer.mozilla.org/en-US/docs/Glossary/ARPA) 21. [ARPANET](https://developer.mozilla.org/en-US/docs/Glossary/Arpanet) 22. [Array](https://developer.mozilla.org/en-US/docs/Glossary/Array) 23. [ASCII](https://developer.mozilla.org/en-US/docs/Glossary/ASCII) 24. [Aspect ratio](https://developer.mozilla.org/en-US/docs/Glossary/Aspect_ratio) 25. [Asynchronous](https://developer.mozilla.org/en-US/docs/Glossary/Asynchronous) 26. [ATAG](https://developer.mozilla.org/en-US/docs/Glossary/ATAG) 27. [Attribute](https://developer.mozilla.org/en-US/docs/Glossary/Attribute) 28. [Authentication](https://developer.mozilla.org/en-US/docs/Glossary/Authentication) 29. [Authenticator](https://developer.mozilla.org/en-US/docs/Glossary/Authenticator) 30. [Bandwidth](https://developer.mozilla.org/en-US/docs/Glossary/Bandwidth) 31. [Base64](https://developer.mozilla.org/en-US/docs/Glossary/Base64) 32. [Baseline](https://developer.mozilla.org/en-US/docs/Glossary/Baseline) 1. [Baseline (compatibility)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Compatibility) 2. [Baseline (typography)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Typography) 33. [BCP 47 language tag](https://developer.mozilla.org/en-US/docs/Glossary/BCP_47_language_tag) 34. [Beacon](https://developer.mozilla.org/en-US/docs/Glossary/Beacon) 35. [Bézier curve](https://developer.mozilla.org/en-US/docs/Glossary/Bezier_curve) 36. [bfcache](https://developer.mozilla.org/en-US/docs/Glossary/bfcache) 37. [BiDi](https://developer.mozilla.org/en-US/docs/Glossary/BiDi) 38. [BigInt](https://developer.mozilla.org/en-US/docs/Glossary/BigInt) 39. [Binding](https://developer.mozilla.org/en-US/docs/Glossary/Binding) 40. [Bitwise flags](https://developer.mozilla.org/en-US/docs/Glossary/Bitwise_flags) 41. [Blink](https://developer.mozilla.org/en-US/docs/Glossary/Blink) 42. [blink element (<blink> tag)](https://developer.mozilla.org/en-US/docs/Glossary/blink_element) 43. [Block](https://developer.mozilla.org/en-US/docs/Glossary/Block) 1. [Block (CSS)](https://developer.mozilla.org/en-US/docs/Glossary/Block/CSS) 2. [Block (scripting)](https://developer.mozilla.org/en-US/docs/Glossary/Block/Scripting) 44. [Block cipher mode of operation](https://developer.mozilla.org/en-US/docs/Glossary/Block_cipher_mode_of_operation) 45. [Block-level content](https://developer.mozilla.org/en-US/docs/Glossary/Block-level_content) 46. [Boolean](https://developer.mozilla.org/en-US/docs/Glossary/Boolean) 1. [Boolean (JavaScript)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/JavaScript) 2. [Boolean attribute (ARIA)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/ARIA) 3. [Boolean attribute (HTML)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/HTML) 47. [Bounding box](https://developer.mozilla.org/en-US/docs/Glossary/Bounding_box) 48. [Breadcrumb](https://developer.mozilla.org/en-US/docs/Glossary/Breadcrumb) 49. [Brotli


id: value-glossary-mdn-20260505-0
file: data/developer.mozilla.org/en-US/docs/Glossary/Value-0.md
category: reference
title: Value - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/Value
date_saved: 2026-05-05T05:48:24.261151+00:00
instance: kb-cron
parent: value-glossary-mdn-20260505-0
summary:
* [Skip to main content](https://developer.mozilla.org/en-US/docs/Glossary/Value#content) * [Skip to search](https://developer.mozilla.org/en-US/docs/Glossary/Value#search) [ MDN ](https://developer.mozilla.org/en-US/) HTML [HTML: Markup language](https://developer.mozilla.org/en-US/docs/Web/HTML) HTML reference * [Elements](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements) * [Global attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes) * [Attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Attributes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference "See all HTML references") HTML guides * [Responsive images](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Responsive_images) * [HTML cheatsheet](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Cheatsheet) * [Date & time formats](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Date_and_time_formats) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides "See all HTML guides") Markup languages * [SVG](https://developer.mozilla.org/en-US/docs/Web/SVG) * [MathML](https://developer.mozilla.org/en-US/docs/Web/MathML) * [XML](https://developer.mozilla.org/en-US/docs/Web/XML) CSS [CSS: Styling language](https://developer.mozilla.org/en-US/docs/Web/CSS) CSS reference * [Properties](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties) * [Selectors](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors) * [At-rules](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/At-rules) * [Values](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference "See all CSS references") CSS guides * [Box model](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Box_model/Introduction) * [Animations](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Animations/Using) * [Flexbox](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Flexible_box_layout/Basic_concepts) * [Colors](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Colors/Applying_color) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides "See all CSS guides") Layout cookbook * [Column layouts](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Column_layouts) * [Centering an element](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Center_an_element) * [Card component](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Card) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook) JavaScriptJS [JavaScript: Scripting language](https://developer.mozilla.org/en-US/docs/Web/JavaScript) JS reference * [Standard built-in objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects) * [Expressions & operators](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators) * [Statements & declarations](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements) * [Functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference "See all JavaScript references") JS guides * [Control flow & error handing](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Control_flow_and_error_handling) * [Loops and iteration](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration) * [Working with objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_objects) * [Using classes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_classes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide "See all JavaScript guides") Web APIs [Web APIs: Programming interfaces](https://developer.mozilla.org/en-US/docs/Web/API) Web API reference * [File system API](https://developer.mozilla.org/en-US/docs/Web/API/File_System_API) * [Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) * [Geolocation API](https://developer.mozilla.org/en-US/docs/Web/API/Geolocation_API) * [HTML DOM API](https://developer.mozilla.org/en-US/docs/Web/API/HTML_DOM_API) * [Push API](https://developer.mozilla.org/en-US/docs/Web/API/Push_API) * [Service worker API](https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API) * [See all…](https://developer.mozilla.org/en-US/docs/Web/API


id: value-glossary-mdn-20260505-1
file: data/developer.mozilla.org/en-US/docs/Glossary/Value-1.md
category: reference
title: Value - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/Value
date_saved: 2026-05-05T05:48:24.261151+00:00
instance: kb-cron
parent: value-glossary-mdn-20260505-0
summary:
## Help improve MDN [Learn how to contribute](https://developer.mozilla.org/en-US/docs/MDN/Community/Getting_started) This page was last modified on Nov 7, 2025 by [MDN contributors](https://developer.mozilla.org/en-US/docs/Glossary/Value/contributors.txt). [View this page on GitHub](https://github.com/mdn/content/blob/main/files/en-us/glossary/value/index.md?plain=1 "Folder: en-us/glossary/value \(Opens in a new tab\)") • [Report a problem with this content](https://github.com/mdn/content/issues/new?template=page-report.yml&mdn-url=https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FValue&metadata=%3C%21--+Do+not+make+changes+below+this+line+--%3E%0A%3Cdetails%3E%0A%3Csummary%3EPage+report+details%3C%2Fsummary%3E%0A%0A*+Folder%3A+%60en-us%2Fglossary%2Fvalue%60%0A*+MDN+URL%3A+https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FValue%0A*+GitHub+URL%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fblob%2Fmain%2Ffiles%2Fen-us%2Fglossary%2Fvalue%2Findex.md%0A*+Last+commit%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fcommit%2F85fccefc8066bd49af4ddafc12c77f35265c7e2d%0A*+Document+last+modified%3A+2025-11-07T15%3A58%3A06.000Z%0A%0A%3C%2Fdetails%3E "This will take you to GitHub to file a new issue.") 1. [Glossary](https://developer.mozilla.org/en-US/docs/Glossary) 2. 1. [Abstraction](https://developer.mozilla.org/en-US/docs/Glossary/Abstraction) 2. [Accent](https://developer.mozilla.org/en-US/docs/Glossary/Accent) 3. [Accessibility](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility) 4. [Accessibility tree](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility_tree) 5. [Accessible description](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_description) 6. [Accessible name](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_name) 7. [Adobe Flash](https://developer.mozilla.org/en-US/docs/Glossary/Adobe_Flash) 8. [Advance measure](https://developer.mozilla.org/en-US/docs/Glossary/Advance_measure) 9. [Ajax](https://developer.mozilla.org/en-US/docs/Glossary/AJAX) 10. [Algorithm](https://developer.mozilla.org/en-US/docs/Glossary/Algorithm) 11. [Alignment container](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Container) 12. [Alignment subject](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Subject) 13. [Alpha (alpha channel)](https://developer.mozilla.org/en-US/docs/Glossary/Alpha) 14. [ALPN](https://developer.mozilla.org/en-US/docs/Glossary/ALPN) 15. [API](https://developer.mozilla.org/en-US/docs/Glossary/API) 16. [Apple Safari](https://developer.mozilla.org/en-US/docs/Glossary/Apple_Safari) 17. [Application context](https://developer.mozilla.org/en-US/docs/Glossary/Application_context) 18. [Argument](https://developer.mozilla.org/en-US/docs/Glossary/Argument) 19. [ARIA](https://developer.mozilla.org/en-US/docs/Glossary/ARIA) 20. [ARPA](https://developer.mozilla.org/en-US/docs/Glossary/ARPA) 21. [ARPANET](https://developer.mozilla.org/en-US/docs/Glossary/Arpanet) 22. [Array](https://developer.mozilla.org/en-US/docs/Glossary/Array) 23. [ASCII](https://developer.mozilla.org/en-US/docs/Glossary/ASCII) 24. [Aspect ratio](https://developer.mozilla.org/en-US/docs/Glossary/Aspect_ratio) 25. [Asynchronous](https://developer.mozilla.org/en-US/docs/Glossary/Asynchronous) 26. [ATAG](https://developer.mozilla.org/en-US/docs/Glossary/ATAG) 27. [Attribute](https://developer.mozilla.org/en-US/docs/Glossary/Attribute) 28. [Authentication](https://developer.mozilla.org/en-US/docs/Glossary/Authentication) 29. [Authenticator](https://developer.mozilla.org/en-US/docs/Glossary/Authenticator) 30. [Bandwidth](https://developer.mozilla.org/en-US/docs/Glossary/Bandwidth) 31. [Base64](https://developer.mozilla.org/en-US/docs/Glossary/Base64) 32. [Baseline](https://developer.mozilla.org/en-US/docs/Glossary/Baseline) 1. [Baseline (compatibility)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Compatibility) 2. [Baseline (typography)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Typography) 33. [BCP 47 language tag](https://developer.mozilla.org/en-US/docs/Glossary/BCP_47_language_tag) 34. [Beacon](https://developer.mozilla.org/en-US/docs/Glossary/Beacon) 35. [Bézier curve](https://developer.mozilla.org/en-US/docs/Glossary/Bezier_curve) 36. [bfcache](https://developer.mozilla.org/en-US/docs/Glossary/bfcache) 37. [BiDi](https://developer.mozilla.org/en-US/docs/Glossary/BiDi) 38. [BigInt](https://developer.mozilla.org/en-US/docs/Glossary/BigInt) 39. [Binding](https://developer.mozilla.org/en-US/docs/Glossary/Binding) 40. [Bitwise flags](https://developer.mozilla.org/en-US/docs/Glossary/Bitwise_flags) 41. [Blink](https://developer.mozilla.org/en-US/docs/Glossary/Blink) 42. [blink element (<blink> tag)](https://developer.mozilla.org/en-US/docs/Glossary/blink_element) 43. [Block](https://developer.mozilla.org/en-US/docs/Glossary/Block) 1. [Block (CSS)](https://developer.mozilla.org/en-US/docs/Glossary/Block/CSS) 2. [Block (scripting)](https://developer.mozilla.org/en-US/docs/Glossary/Block/Scripting) 44. [Block cipher mode of operation](https://developer.mozilla.org/en-US/docs/Glossary/Block_cipher_mode_of_operation) 45. [Block-level content](https://developer.mozilla.org/en-US/docs/Glossary/Block-level_content) 46. [Boolean](https://developer.mozilla.org/en-US/docs/Glossary/Boolean) 1. [Boolean (JavaScript)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/JavaScript) 2. [Boolean attribute (ARIA)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/ARIA) 3. [Boolean attribute (HTML)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/HTML) 47. [Bounding box](https://developer.mozilla.org/en-US/docs/Glossary/Bounding_box) 48. [Breadcrumb](https://developer.mozilla.org/en-US/docs/Glossary/Breadcrumb) 49. [Brotli


id: variable-glossary-mdn-20260505-0
file: data/developer.mozilla.org/en-US/docs/Glossary/Variable-0.md
category: reference
title: Variable - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/Variable
date_saved: 2026-05-05T05:48:27.046204+00:00
instance: kb-cron
parent: variable-glossary-mdn-20260505-0
summary:
* [Skip to main content](https://developer.mozilla.org/en-US/docs/Glossary/Variable#content) * [Skip to search](https://developer.mozilla.org/en-US/docs/Glossary/Variable#search) [ MDN ](https://developer.mozilla.org/en-US/) HTML [HTML: Markup language](https://developer.mozilla.org/en-US/docs/Web/HTML) HTML reference * [Elements](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements) * [Global attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes) * [Attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Attributes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference "See all HTML references") HTML guides * [Responsive images](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Responsive_images) * [HTML cheatsheet](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Cheatsheet) * [Date & time formats](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Date_and_time_formats) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides "See all HTML guides") Markup languages * [SVG](https://developer.mozilla.org/en-US/docs/Web/SVG) * [MathML](https://developer.mozilla.org/en-US/docs/Web/MathML) * [XML](https://developer.mozilla.org/en-US/docs/Web/XML) CSS [CSS: Styling language](https://developer.mozilla.org/en-US/docs/Web/CSS) CSS reference * [Properties](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties) * [Selectors](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors) * [At-rules](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/At-rules) * [Values](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference "See all CSS references") CSS guides * [Box model](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Box_model/Introduction) * [Animations](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Animations/Using) * [Flexbox](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Flexible_box_layout/Basic_concepts) * [Colors](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Colors/Applying_color) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides "See all CSS guides") Layout cookbook * [Column layouts](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Column_layouts) * [Centering an element](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Center_an_element) * [Card component](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Card) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook) JavaScriptJS [JavaScript: Scripting language](https://developer.mozilla.org/en-US/docs/Web/JavaScript) JS reference * [Standard built-in objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects) * [Expressions & operators](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators) * [Statements & declarations](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements) * [Functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference "See all JavaScript references") JS guides * [Control flow & error handing](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Control_flow_and_error_handling) * [Loops and iteration](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration) * [Working with objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_objects) * [Using classes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_classes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide "See all JavaScript guides") Web APIs [Web APIs: Programming interfaces](https://developer.mozilla.org/en-US/docs/Web/API) Web API reference * [File system API](https://developer.mozilla.org/en-US/docs/Web/API/File_System_API) * [Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) * [Geolocation API](https://developer.mozilla.org/en-US/docs/Web/API/Geolocation_API) * [HTML DOM API](https://developer.mozilla.org/en-US/docs/Web/API/HTML_DOM_API) * [Push API](https://developer.mozilla.org/en-US/docs/Web/API/Push_API) * [Service worker API](https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API) * [See all…](https://developer.mozilla.org/en-US/docs/Web/API


id: variable-glossary-mdn-20260505-1
file: data/developer.mozilla.org/en-US/docs/Glossary/Variable-1.md
category: reference
title: Variable - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/Variable
date_saved: 2026-05-05T05:48:27.046204+00:00
instance: kb-cron
parent: variable-glossary-mdn-20260505-0
summary:
## Help improve MDN [Learn how to contribute](https://developer.mozilla.org/en-US/docs/MDN/Community/Getting_started) This page was last modified on Jul 11, 2025 by [MDN contributors](https://developer.mozilla.org/en-US/docs/Glossary/Variable/contributors.txt). [View this page on GitHub](https://github.com/mdn/content/blob/main/files/en-us/glossary/variable/index.md?plain=1 "Folder: en-us/glossary/variable \(Opens in a new tab\)") • [Report a problem with this content](https://github.com/mdn/content/issues/new?template=page-report.yml&mdn-url=https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FVariable&metadata=%3C%21--+Do+not+make+changes+below+this+line+--%3E%0A%3Cdetails%3E%0A%3Csummary%3EPage+report+details%3C%2Fsummary%3E%0A%0A*+Folder%3A+%60en-us%2Fglossary%2Fvariable%60%0A*+MDN+URL%3A+https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FVariable%0A*+GitHub+URL%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fblob%2Fmain%2Ffiles%2Fen-us%2Fglossary%2Fvariable%2Findex.md%0A*+Last+commit%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fcommit%2F2547f622337d6cbf8c3794776b17ed377d6aad57%0A*+Document+last+modified%3A+2025-07-11T14%3A45%3A59.000Z%0A%0A%3C%2Fdetails%3E "This will take you to GitHub to file a new issue.") 1. [Glossary](https://developer.mozilla.org/en-US/docs/Glossary) 2. 1. [Abstraction](https://developer.mozilla.org/en-US/docs/Glossary/Abstraction) 2. [Accent](https://developer.mozilla.org/en-US/docs/Glossary/Accent) 3. [Accessibility](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility) 4. [Accessibility tree](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility_tree) 5. [Accessible description](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_description) 6. [Accessible name](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_name) 7. [Adobe Flash](https://developer.mozilla.org/en-US/docs/Glossary/Adobe_Flash) 8. [Advance measure](https://developer.mozilla.org/en-US/docs/Glossary/Advance_measure) 9. [Ajax](https://developer.mozilla.org/en-US/docs/Glossary/AJAX) 10. [Algorithm](https://developer.mozilla.org/en-US/docs/Glossary/Algorithm) 11. [Alignment container](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Container) 12. [Alignment subject](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Subject) 13. [Alpha (alpha channel)](https://developer.mozilla.org/en-US/docs/Glossary/Alpha) 14. [ALPN](https://developer.mozilla.org/en-US/docs/Glossary/ALPN) 15. [API](https://developer.mozilla.org/en-US/docs/Glossary/API) 16. [Apple Safari](https://developer.mozilla.org/en-US/docs/Glossary/Apple_Safari) 17. [Application context](https://developer.mozilla.org/en-US/docs/Glossary/Application_context) 18. [Argument](https://developer.mozilla.org/en-US/docs/Glossary/Argument) 19. [ARIA](https://developer.mozilla.org/en-US/docs/Glossary/ARIA) 20. [ARPA](https://developer.mozilla.org/en-US/docs/Glossary/ARPA) 21. [ARPANET](https://developer.mozilla.org/en-US/docs/Glossary/Arpanet) 22. [Array](https://developer.mozilla.org/en-US/docs/Glossary/Array) 23. [ASCII](https://developer.mozilla.org/en-US/docs/Glossary/ASCII) 24. [Aspect ratio](https://developer.mozilla.org/en-US/docs/Glossary/Aspect_ratio) 25. [Asynchronous](https://developer.mozilla.org/en-US/docs/Glossary/Asynchronous) 26. [ATAG](https://developer.mozilla.org/en-US/docs/Glossary/ATAG) 27. [Attribute](https://developer.mozilla.org/en-US/docs/Glossary/Attribute) 28. [Authentication](https://developer.mozilla.org/en-US/docs/Glossary/Authentication) 29. [Authenticator](https://developer.mozilla.org/en-US/docs/Glossary/Authenticator) 30. [Bandwidth](https://developer.mozilla.org/en-US/docs/Glossary/Bandwidth) 31. [Base64](https://developer.mozilla.org/en-US/docs/Glossary/Base64) 32. [Baseline](https://developer.mozilla.org/en-US/docs/Glossary/Baseline) 1. [Baseline (compatibility)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Compatibility) 2. [Baseline (typography)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Typography) 33. [BCP 47 language tag](https://developer.mozilla.org/en-US/docs/Glossary/BCP_47_language_tag) 34. [Beacon](https://developer.mozilla.org/en-US/docs/Glossary/Beacon) 35. [Bézier curve](https://developer.mozilla.org/en-US/docs/Glossary/Bezier_curve) 36. [bfcache](https://developer.mozilla.org/en-US/docs/Glossary/bfcache) 37. [BiDi](https://developer.mozilla.org/en-US/docs/Glossary/BiDi) 38. [BigInt](https://developer.mozilla.org/en-US/docs/Glossary/BigInt) 39. [Binding](https://developer.mozilla.org/en-US/docs/Glossary/Binding) 40. [Bitwise flags](https://developer.mozilla.org/en-US/docs/Glossary/Bitwise_flags) 41. [Blink](https://developer.mozilla.org/en-US/docs/Glossary/Blink) 42. [blink element (<blink> tag)](https://developer.mozilla.org/en-US/docs/Glossary/blink_element) 43. [Block](https://developer.mozilla.org/en-US/docs/Glossary/Block) 1. [Block (CSS)](https://developer.mozilla.org/en-US/docs/Glossary/Block/CSS) 2. [Block (scripting)](https://developer.mozilla.org/en-US/docs/Glossary/Block/Scripting) 44. [Block cipher mode of operation](https://developer.mozilla.org/en-US/docs/Glossary/Block_cipher_mode_of_operation) 45. [Block-level content](https://developer.mozilla.org/en-US/docs/Glossary/Block-level_content) 46. [Boolean](https://developer.mozilla.org/en-US/docs/Glossary/Boolean) 1. [Boolean (JavaScript)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/JavaScript) 2. [Boolean attribute (ARIA)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/ARIA) 3. [Boolean attribute (HTML)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/HTML) 47. [Bounding box](https://developer.mozilla.org/en-US/docs/Glossary/Bounding_box) 48. [Breadcrumb](https://developer.mozilla.org/en-US/docs/Glossary/Breadcrumb) 49. [Brotli


id: vendor-prefix-glossary-mdn-20260505-0
file: data/developer.mozilla.org/en-US/docs/Glossary/Vendor_Prefix-0.md
category: reference
title: Vendor prefix - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/Vendor_Prefix
date_saved: 2026-05-05T05:48:29.514800+00:00
instance: kb-cron
parent: vendor-prefix-glossary-mdn-20260505-0
summary:
* [Skip to main content](https://developer.mozilla.org/en-US/docs/Glossary/Vendor_Prefix#content) * [Skip to search](https://developer.mozilla.org/en-US/docs/Glossary/Vendor_Prefix#search) [ MDN ](https://developer.mozilla.org/en-US/) HTML [HTML: Markup language](https://developer.mozilla.org/en-US/docs/Web/HTML) HTML reference * [Elements](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements) * [Global attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes) * [Attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Attributes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference "See all HTML references") HTML guides * [Responsive images](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Responsive_images) * [HTML cheatsheet](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Cheatsheet) * [Date & time formats](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Date_and_time_formats) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides "See all HTML guides") Markup languages * [SVG](https://developer.mozilla.org/en-US/docs/Web/SVG) * [MathML](https://developer.mozilla.org/en-US/docs/Web/MathML) * [XML](https://developer.mozilla.org/en-US/docs/Web/XML) CSS [CSS: Styling language](https://developer.mozilla.org/en-US/docs/Web/CSS) CSS reference * [Properties](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties) * [Selectors](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors) * [At-rules](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/At-rules) * [Values](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference "See all CSS references") CSS guides * [Box model](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Box_model/Introduction) * [Animations](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Animations/Using) * [Flexbox](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Flexible_box_layout/Basic_concepts) * [Colors](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Colors/Applying_color) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides "See all CSS guides") Layout cookbook * [Column layouts](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Column_layouts) * [Centering an element](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Center_an_element) * [Card component](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Card) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook) JavaScriptJS [JavaScript: Scripting language](https://developer.mozilla.org/en-US/docs/Web/JavaScript) JS reference * [Standard built-in objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects) * [Expressions & operators](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators) * [Statements & declarations](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements) * [Functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference "See all JavaScript references") JS guides * [Control flow & error handing](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Control_flow_and_error_handling) * [Loops and iteration](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration) * [Working with objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_objects) * [Using classes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_classes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide "See all JavaScript guides") Web APIs [Web APIs: Programming interfaces](https://developer.mozilla.org/en-US/docs/Web/API) Web API reference * [File system API](https://developer.mozilla.org/en-US/docs/Web/API/File_System_API) * [Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) * [Geolocation API](https://developer.mozilla.org/en-US/docs/Web/API/Geolocation_API) * [HTML DOM API](https://developer.mozilla.org/en-US/docs/Web/API/HTML_DOM_API) * [Push API](https://developer.mozilla.org/en-US/docs/Web/API/Push_API) * [Service worker API](https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API) * [See all…](https://developer.mozilla.org/en-US/docs/Web/API


id: vendor-prefix-glossary-mdn-20260505-1
file: data/developer.mozilla.org/en-US/docs/Glossary/Vendor_Prefix-1.md
category: reference
title: Vendor prefix - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/Vendor_Prefix
date_saved: 2026-05-05T05:48:29.514800+00:00
instance: kb-cron
parent: vendor-prefix-glossary-mdn-20260505-0
summary:
## Help improve MDN [Learn how to contribute](https://developer.mozilla.org/en-US/docs/MDN/Community/Getting_started) This page was last modified on Oct 30, 2025 by [MDN contributors](https://developer.mozilla.org/en-US/docs/Glossary/Vendor_Prefix/contributors.txt). [View this page on GitHub](https://github.com/mdn/content/blob/main/files/en-us/glossary/vendor_prefix/index.md?plain=1 "Folder: en-us/glossary/vendor_prefix \(Opens in a new tab\)") • [Report a problem with this content](https://github.com/mdn/content/issues/new?template=page-report.yml&mdn-url=https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FVendor_Prefix&metadata=%3C%21--+Do+not+make+changes+below+this+line+--%3E%0A%3Cdetails%3E%0A%3Csummary%3EPage+report+details%3C%2Fsummary%3E%0A%0A*+Folder%3A+%60en-us%2Fglossary%2Fvendor_prefix%60%0A*+MDN+URL%3A+https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FVendor_Prefix%0A*+GitHub+URL%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fblob%2Fmain%2Ffiles%2Fen-us%2Fglossary%2Fvendor_prefix%2Findex.md%0A*+Last+commit%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fcommit%2F2d78abb3e793352e24e976ce0e68c08d817bd7f3%0A*+Document+last+modified%3A+2025-10-30T16%3A59%3A53.000Z%0A%0A%3C%2Fdetails%3E "This will take you to GitHub to file a new issue.") 1. [Glossary](https://developer.mozilla.org/en-US/docs/Glossary) 2. 1. [Abstraction](https://developer.mozilla.org/en-US/docs/Glossary/Abstraction) 2. [Accent](https://developer.mozilla.org/en-US/docs/Glossary/Accent) 3. [Accessibility](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility) 4. [Accessibility tree](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility_tree) 5. [Accessible description](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_description) 6. [Accessible name](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_name) 7. [Adobe Flash](https://developer.mozilla.org/en-US/docs/Glossary/Adobe_Flash) 8. [Advance measure](https://developer.mozilla.org/en-US/docs/Glossary/Advance_measure) 9. [Ajax](https://developer.mozilla.org/en-US/docs/Glossary/AJAX) 10. [Algorithm](https://developer.mozilla.org/en-US/docs/Glossary/Algorithm) 11. [Alignment container](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Container) 12. [Alignment subject](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Subject) 13. [Alpha (alpha channel)](https://developer.mozilla.org/en-US/docs/Glossary/Alpha) 14. [ALPN](https://developer.mozilla.org/en-US/docs/Glossary/ALPN) 15. [API](https://developer.mozilla.org/en-US/docs/Glossary/API) 16. [Apple Safari](https://developer.mozilla.org/en-US/docs/Glossary/Apple_Safari) 17. [Application context](https://developer.mozilla.org/en-US/docs/Glossary/Application_context) 18. [Argument](https://developer.mozilla.org/en-US/docs/Glossary/Argument) 19. [ARIA](https://developer.mozilla.org/en-US/docs/Glossary/ARIA) 20. [ARPA](https://developer.mozilla.org/en-US/docs/Glossary/ARPA) 21. [ARPANET](https://developer.mozilla.org/en-US/docs/Glossary/Arpanet) 22. [Array](https://developer.mozilla.org/en-US/docs/Glossary/Array) 23. [ASCII](https://developer.mozilla.org/en-US/docs/Glossary/ASCII) 24. [Aspect ratio](https://developer.mozilla.org/en-US/docs/Glossary/Aspect_ratio) 25. [Asynchronous](https://developer.mozilla.org/en-US/docs/Glossary/Asynchronous) 26. [ATAG](https://developer.mozilla.org/en-US/docs/Glossary/ATAG) 27. [Attribute](https://developer.mozilla.org/en-US/docs/Glossary/Attribute) 28. [Authentication](https://developer.mozilla.org/en-US/docs/Glossary/Authentication) 29. [Authenticator](https://developer.mozilla.org/en-US/docs/Glossary/Authenticator) 30. [Bandwidth](https://developer.mozilla.org/en-US/docs/Glossary/Bandwidth) 31. [Base64](https://developer.mozilla.org/en-US/docs/Glossary/Base64) 32. [Baseline](https://developer.mozilla.org/en-US/docs/Glossary/Baseline) 1. [Baseline (compatibility)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Compatibility) 2. [Baseline (typography)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Typography) 33. [BCP 47 language tag](https://developer.mozilla.org/en-US/docs/Glossary/BCP_47_language_tag) 34. [Beacon](https://developer.mozilla.org/en-US/docs/Glossary/Beacon) 35. [Bézier curve](https://developer.mozilla.org/en-US/docs/Glossary/Bezier_curve) 36. [bfcache](https://developer.mozilla.org/en-US/docs/Glossary/bfcache) 37. [BiDi](https://developer.mozilla.org/en-US/docs/Glossary/BiDi) 38. [BigInt](https://developer.mozilla.org/en-US/docs/Glossary/BigInt) 39. [Binding](https://developer.mozilla.org/en-US/docs/Glossary/Binding) 40. [Bitwise flags](https://developer.mozilla.org/en-US/docs/Glossary/Bitwise_flags) 41. [Blink](https://developer.mozilla.org/en-US/docs/Glossary/Blink) 42. [blink element (<blink> tag)](https://developer.mozilla.org/en-US/docs/Glossary/blink_element) 43. [Block](https://developer.mozilla.org/en-US/docs/Glossary/Block) 1. [Block (CSS)](https://developer.mozilla.org/en-US/docs/Glossary/Block/CSS) 2. [Block (scripting)](https://developer.mozilla.org/en-US/docs/Glossary/Block/Scripting) 44. [Block cipher mode of operation](https://developer.mozilla.org/en-US/docs/Glossary/Block_cipher_mode_of_operation) 45. [Block-level content](https://developer.mozilla.org/en-US/docs/Glossary/Block-level_content) 46. [Boolean](https://developer.mozilla.org/en-US/docs/Glossary/Boolean) 1. [Boolean (JavaScript)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/JavaScript) 2. [Boolean attribute (ARIA)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/ARIA) 3. [Boolean attribute (HTML)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/HTML) 47. [Bounding box](https://developer.mozilla.org/en-US/docs/Glossary/Bounding_box) 48. [Breadcrumb](https://developer.mozilla.org/en-US/docs/Glossary/Breadcrumb) 49. [Brotli


id: viewport-glossary-mdn-20260505-0
file: data/developer.mozilla.org/en-US/docs/Glossary/Viewport-0.md
category: reference
title: Viewport - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/Viewport
date_saved: 2026-05-05T05:48:32.118404+00:00
instance: kb-cron
parent: viewport-glossary-mdn-20260505-0
summary:
* [Skip to main content](https://developer.mozilla.org/en-US/docs/Glossary/Viewport#content) * [Skip to search](https://developer.mozilla.org/en-US/docs/Glossary/Viewport#search) [ MDN ](https://developer.mozilla.org/en-US/) HTML [HTML: Markup language](https://developer.mozilla.org/en-US/docs/Web/HTML) HTML reference * [Elements](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements) * [Global attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes) * [Attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Attributes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference "See all HTML references") HTML guides * [Responsive images](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Responsive_images) * [HTML cheatsheet](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Cheatsheet) * [Date & time formats](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Date_and_time_formats) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides "See all HTML guides") Markup languages * [SVG](https://developer.mozilla.org/en-US/docs/Web/SVG) * [MathML](https://developer.mozilla.org/en-US/docs/Web/MathML) * [XML](https://developer.mozilla.org/en-US/docs/Web/XML) CSS [CSS: Styling language](https://developer.mozilla.org/en-US/docs/Web/CSS) CSS reference * [Properties](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties) * [Selectors](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors) * [At-rules](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/At-rules) * [Values](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference "See all CSS references") CSS guides * [Box model](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Box_model/Introduction) * [Animations](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Animations/Using) * [Flexbox](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Flexible_box_layout/Basic_concepts) * [Colors](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Colors/Applying_color) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides "See all CSS guides") Layout cookbook * [Column layouts](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Column_layouts) * [Centering an element](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Center_an_element) * [Card component](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Card) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook) JavaScriptJS [JavaScript: Scripting language](https://developer.mozilla.org/en-US/docs/Web/JavaScript) JS reference * [Standard built-in objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects) * [Expressions & operators](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators) * [Statements & declarations](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements) * [Functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference "See all JavaScript references") JS guides * [Control flow & error handing](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Control_flow_and_error_handling) * [Loops and iteration](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration) * [Working with objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_objects) * [Using classes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_classes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide "See all JavaScript guides") Web APIs [Web APIs: Programming interfaces](https://developer.mozilla.org/en-US/docs/Web/API) Web API reference * [File system API](https://developer.mozilla.org/en-US/docs/Web/API/File_System_API) * [Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) * [Geolocation API](https://developer.mozilla.org/en-US/docs/Web/API/Geolocation_API) * [HTML DOM API](https://developer.mozilla.org/en-US/docs/Web/API/HTML_DOM_API) * [Push API](https://developer.mozilla.org/en-US/docs/Web/API/Push_API) * [Service worker API](https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API) * [See all…](https://developer.mozilla.org/en-US/docs/Web/API


id: viewport-glossary-mdn-20260505-1
file: data/developer.mozilla.org/en-US/docs/Glossary/Viewport-1.md
category: reference
title: Viewport - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/Viewport
date_saved: 2026-05-05T05:48:32.118404+00:00
instance: kb-cron
parent: viewport-glossary-mdn-20260505-0
summary:
## Help improve MDN [Learn how to contribute](https://developer.mozilla.org/en-US/docs/MDN/Community/Getting_started) This page was last modified on Nov 19, 2025 by [MDN contributors](https://developer.mozilla.org/en-US/docs/Glossary/Viewport/contributors.txt). [View this page on GitHub](https://github.com/mdn/content/blob/main/files/en-us/glossary/viewport/index.md?plain=1 "Folder: en-us/glossary/viewport \(Opens in a new tab\)") • [Report a problem with this content](https://github.com/mdn/content/issues/new?template=page-report.yml&mdn-url=https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FViewport&metadata=%3C%21--+Do+not+make+changes+below+this+line+--%3E%0A%3Cdetails%3E%0A%3Csummary%3EPage+report+details%3C%2Fsummary%3E%0A%0A*+Folder%3A+%60en-us%2Fglossary%2Fviewport%60%0A*+MDN+URL%3A+https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FViewport%0A*+GitHub+URL%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fblob%2Fmain%2Ffiles%2Fen-us%2Fglossary%2Fviewport%2Findex.md%0A*+Last+commit%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fcommit%2F9be502ee0f8b030908e59d30884190281acb8054%0A*+Document+last+modified%3A+2025-11-19T16%3A16%3A06.000Z%0A%0A%3C%2Fdetails%3E "This will take you to GitHub to file a new issue.") 1. [Glossary](https://developer.mozilla.org/en-US/docs/Glossary) 2. 1. [Abstraction](https://developer.mozilla.org/en-US/docs/Glossary/Abstraction) 2. [Accent](https://developer.mozilla.org/en-US/docs/Glossary/Accent) 3. [Accessibility](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility) 4. [Accessibility tree](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility_tree) 5. [Accessible description](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_description) 6. [Accessible name](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_name) 7. [Adobe Flash](https://developer.mozilla.org/en-US/docs/Glossary/Adobe_Flash) 8. [Advance measure](https://developer.mozilla.org/en-US/docs/Glossary/Advance_measure) 9. [Ajax](https://developer.mozilla.org/en-US/docs/Glossary/AJAX) 10. [Algorithm](https://developer.mozilla.org/en-US/docs/Glossary/Algorithm) 11. [Alignment container](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Container) 12. [Alignment subject](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Subject) 13. [Alpha (alpha channel)](https://developer.mozilla.org/en-US/docs/Glossary/Alpha) 14. [ALPN](https://developer.mozilla.org/en-US/docs/Glossary/ALPN) 15. [API](https://developer.mozilla.org/en-US/docs/Glossary/API) 16. [Apple Safari](https://developer.mozilla.org/en-US/docs/Glossary/Apple_Safari) 17. [Application context](https://developer.mozilla.org/en-US/docs/Glossary/Application_context) 18. [Argument](https://developer.mozilla.org/en-US/docs/Glossary/Argument) 19. [ARIA](https://developer.mozilla.org/en-US/docs/Glossary/ARIA) 20. [ARPA](https://developer.mozilla.org/en-US/docs/Glossary/ARPA) 21. [ARPANET](https://developer.mozilla.org/en-US/docs/Glossary/Arpanet) 22. [Array](https://developer.mozilla.org/en-US/docs/Glossary/Array) 23. [ASCII](https://developer.mozilla.org/en-US/docs/Glossary/ASCII) 24. [Aspect ratio](https://developer.mozilla.org/en-US/docs/Glossary/Aspect_ratio) 25. [Asynchronous](https://developer.mozilla.org/en-US/docs/Glossary/Asynchronous) 26. [ATAG](https://developer.mozilla.org/en-US/docs/Glossary/ATAG) 27. [Attribute](https://developer.mozilla.org/en-US/docs/Glossary/Attribute) 28. [Authentication](https://developer.mozilla.org/en-US/docs/Glossary/Authentication) 29. [Authenticator](https://developer.mozilla.org/en-US/docs/Glossary/Authenticator) 30. [Bandwidth](https://developer.mozilla.org/en-US/docs/Glossary/Bandwidth) 31. [Base64](https://developer.mozilla.org/en-US/docs/Glossary/Base64) 32. [Baseline](https://developer.mozilla.org/en-US/docs/Glossary/Baseline) 1. [Baseline (compatibility)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Compatibility) 2. [Baseline (typography)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Typography) 33. [BCP 47 language tag](https://developer.mozilla.org/en-US/docs/Glossary/BCP_47_language_tag) 34. [Beacon](https://developer.mozilla.org/en-US/docs/Glossary/Beacon) 35. [Bézier curve](https://developer.mozilla.org/en-US/docs/Glossary/Bezier_curve) 36. [bfcache](https://developer.mozilla.org/en-US/docs/Glossary/bfcache) 37. [BiDi](https://developer.mozilla.org/en-US/docs/Glossary/BiDi) 38. [BigInt](https://developer.mozilla.org/en-US/docs/Glossary/BigInt) 39. [Binding](https://developer.mozilla.org/en-US/docs/Glossary/Binding) 40. [Bitwise flags](https://developer.mozilla.org/en-US/docs/Glossary/Bitwise_flags) 41. [Blink](https://developer.mozilla.org/en-US/docs/Glossary/Blink) 42. [blink element (<blink> tag)](https://developer.mozilla.org/en-US/docs/Glossary/blink_element) 43. [Block](https://developer.mozilla.org/en-US/docs/Glossary/Block) 1. [Block (CSS)](https://developer.mozilla.org/en-US/docs/Glossary/Block/CSS) 2. [Block (scripting)](https://developer.mozilla.org/en-US/docs/Glossary/Block/Scripting) 44. [Block cipher mode of operation](https://developer.mozilla.org/en-US/docs/Glossary/Block_cipher_mode_of_operation) 45. [Block-level content](https://developer.mozilla.org/en-US/docs/Glossary/Block-level_content) 46. [Boolean](https://developer.mozilla.org/en-US/docs/Glossary/Boolean) 1. [Boolean (JavaScript)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/JavaScript) 2. [Boolean attribute (ARIA)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/ARIA) 3. [Boolean attribute (HTML)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/HTML) 47. [Bounding box](https://developer.mozilla.org/en-US/docs/Glossary/Bounding_box) 48. [Breadcrumb](https://developer.mozilla.org/en-US/docs/Glossary/Breadcrumb) 49. [Brotli


id: visual-viewport-glossary-mdn-20260505-0
file: data/developer.mozilla.org/en-US/docs/Glossary/Visual_Viewport-0.md
category: reference
title: Visual viewport - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/Visual_Viewport
date_saved: 2026-05-05T05:48:34.366900+00:00
instance: kb-cron
parent: visual-viewport-glossary-mdn-20260505-0
summary:
* [Skip to main content](https://developer.mozilla.org/en-US/docs/Glossary/Visual_Viewport#content) * [Skip to search](https://developer.mozilla.org/en-US/docs/Glossary/Visual_Viewport#search) [ MDN ](https://developer.mozilla.org/en-US/) HTML [HTML: Markup language](https://developer.mozilla.org/en-US/docs/Web/HTML) HTML reference * [Elements](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements) * [Global attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes) * [Attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Attributes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference "See all HTML references") HTML guides * [Responsive images](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Responsive_images) * [HTML cheatsheet](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Cheatsheet) * [Date & time formats](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Date_and_time_formats) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides "See all HTML guides") Markup languages * [SVG](https://developer.mozilla.org/en-US/docs/Web/SVG) * [MathML](https://developer.mozilla.org/en-US/docs/Web/MathML) * [XML](https://developer.mozilla.org/en-US/docs/Web/XML) CSS [CSS: Styling language](https://developer.mozilla.org/en-US/docs/Web/CSS) CSS reference * [Properties](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties) * [Selectors](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors) * [At-rules](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/At-rules) * [Values](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference "See all CSS references") CSS guides * [Box model](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Box_model/Introduction) * [Animations](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Animations/Using) * [Flexbox](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Flexible_box_layout/Basic_concepts) * [Colors](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Colors/Applying_color) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides "See all CSS guides") Layout cookbook * [Column layouts](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Column_layouts) * [Centering an element](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Center_an_element) * [Card component](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Card) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook) JavaScriptJS [JavaScript: Scripting language](https://developer.mozilla.org/en-US/docs/Web/JavaScript) JS reference * [Standard built-in objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects) * [Expressions & operators](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators) * [Statements & declarations](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements) * [Functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference "See all JavaScript references") JS guides * [Control flow & error handing](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Control_flow_and_error_handling) * [Loops and iteration](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration) * [Working with objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_objects) * [Using classes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_classes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide "See all JavaScript guides") Web APIs [Web APIs: Programming interfaces](https://developer.mozilla.org/en-US/docs/Web/API) Web API reference * [File system API](https://developer.mozilla.org/en-US/docs/Web/API/File_System_API) * [Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) * [Geolocation API](https://developer.mozilla.org/en-US/docs/Web/API/Geolocation_API) * [HTML DOM API](https://developer.mozilla.org/en-US/docs/Web/API/HTML_DOM_API) * [Push API](https://developer.mozilla.org/en-US/docs/Web/API/Push_API) * [Service worker API](https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API) * [See all…](https://developer.mozilla.org/en-US/docs/Web/API


id: visual-viewport-glossary-mdn-20260505-1
file: data/developer.mozilla.org/en-US/docs/Glossary/Visual_Viewport-1.md
category: reference
title: Visual viewport - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/Visual_Viewport
date_saved: 2026-05-05T05:48:34.366900+00:00
instance: kb-cron
parent: visual-viewport-glossary-mdn-20260505-0
summary:
## Help improve MDN [Learn how to contribute](https://developer.mozilla.org/en-US/docs/MDN/Community/Getting_started) This page was last modified on Nov 19, 2025 by [MDN contributors](https://developer.mozilla.org/en-US/docs/Glossary/Visual_Viewport/contributors.txt). [View this page on GitHub](https://github.com/mdn/content/blob/main/files/en-us/glossary/visual_viewport/index.md?plain=1 "Folder: en-us/glossary/visual_viewport \(Opens in a new tab\)") • [Report a problem with this content](https://github.com/mdn/content/issues/new?template=page-report.yml&mdn-url=https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FVisual_Viewport&metadata=%3C%21--+Do+not+make+changes+below+this+line+--%3E%0A%3Cdetails%3E%0A%3Csummary%3EPage+report+details%3C%2Fsummary%3E%0A%0A*+Folder%3A+%60en-us%2Fglossary%2Fvisual_viewport%60%0A*+MDN+URL%3A+https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FVisual_Viewport%0A*+GitHub+URL%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fblob%2Fmain%2Ffiles%2Fen-us%2Fglossary%2Fvisual_viewport%2Findex.md%0A*+Last+commit%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fcommit%2F9be502ee0f8b030908e59d30884190281acb8054%0A*+Document+last+modified%3A+2025-11-19T16%3A16%3A06.000Z%0A%0A%3C%2Fdetails%3E "This will take you to GitHub to file a new issue.") 1. [Glossary](https://developer.mozilla.org/en-US/docs/Glossary) 2. 1. [Abstraction](https://developer.mozilla.org/en-US/docs/Glossary/Abstraction) 2. [Accent](https://developer.mozilla.org/en-US/docs/Glossary/Accent) 3. [Accessibility](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility) 4. [Accessibility tree](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility_tree) 5. [Accessible description](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_description) 6. [Accessible name](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_name) 7. [Adobe Flash](https://developer.mozilla.org/en-US/docs/Glossary/Adobe_Flash) 8. [Advance measure](https://developer.mozilla.org/en-US/docs/Glossary/Advance_measure) 9. [Ajax](https://developer.mozilla.org/en-US/docs/Glossary/AJAX) 10. [Algorithm](https://developer.mozilla.org/en-US/docs/Glossary/Algorithm) 11. [Alignment container](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Container) 12. [Alignment subject](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Subject) 13. [Alpha (alpha channel)](https://developer.mozilla.org/en-US/docs/Glossary/Alpha) 14. [ALPN](https://developer.mozilla.org/en-US/docs/Glossary/ALPN) 15. [API](https://developer.mozilla.org/en-US/docs/Glossary/API) 16. [Apple Safari](https://developer.mozilla.org/en-US/docs/Glossary/Apple_Safari) 17. [Application context](https://developer.mozilla.org/en-US/docs/Glossary/Application_context) 18. [Argument](https://developer.mozilla.org/en-US/docs/Glossary/Argument) 19. [ARIA](https://developer.mozilla.org/en-US/docs/Glossary/ARIA) 20. [ARPA](https://developer.mozilla.org/en-US/docs/Glossary/ARPA) 21. [ARPANET](https://developer.mozilla.org/en-US/docs/Glossary/Arpanet) 22. [Array](https://developer.mozilla.org/en-US/docs/Glossary/Array) 23. [ASCII](https://developer.mozilla.org/en-US/docs/Glossary/ASCII) 24. [Aspect ratio](https://developer.mozilla.org/en-US/docs/Glossary/Aspect_ratio) 25. [Asynchronous](https://developer.mozilla.org/en-US/docs/Glossary/Asynchronous) 26. [ATAG](https://developer.mozilla.org/en-US/docs/Glossary/ATAG) 27. [Attribute](https://developer.mozilla.org/en-US/docs/Glossary/Attribute) 28. [Authentication](https://developer.mozilla.org/en-US/docs/Glossary/Authentication) 29. [Authenticator](https://developer.mozilla.org/en-US/docs/Glossary/Authenticator) 30. [Bandwidth](https://developer.mozilla.org/en-US/docs/Glossary/Bandwidth) 31. [Base64](https://developer.mozilla.org/en-US/docs/Glossary/Base64) 32. [Baseline](https://developer.mozilla.org/en-US/docs/Glossary/Baseline) 1. [Baseline (compatibility)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Compatibility) 2. [Baseline (typography)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Typography) 33. [BCP 47 language tag](https://developer.mozilla.org/en-US/docs/Glossary/BCP_47_language_tag) 34. [Beacon](https://developer.mozilla.org/en-US/docs/Glossary/Beacon) 35. [Bézier curve](https://developer.mozilla.org/en-US/docs/Glossary/Bezier_curve) 36. [bfcache](https://developer.mozilla.org/en-US/docs/Glossary/bfcache) 37. [BiDi](https://developer.mozilla.org/en-US/docs/Glossary/BiDi) 38. [BigInt](https://developer.mozilla.org/en-US/docs/Glossary/BigInt) 39. [Binding](https://developer.mozilla.org/en-US/docs/Glossary/Binding) 40. [Bitwise flags](https://developer.mozilla.org/en-US/docs/Glossary/Bitwise_flags) 41. [Blink](https://developer.mozilla.org/en-US/docs/Glossary/Blink) 42. [blink element (<blink> tag)](https://developer.mozilla.org/en-US/docs/Glossary/blink_element) 43. [Block](https://developer.mozilla.org/en-US/docs/Glossary/Block) 1. [Block (CSS)](https://developer.mozilla.org/en-US/docs/Glossary/Block/CSS) 2. [Block (scripting)](https://developer.mozilla.org/en-US/docs/Glossary/Block/Scripting) 44. [Block cipher mode of operation](https://developer.mozilla.org/en-US/docs/Glossary/Block_cipher_mode_of_operation) 45. [Block-level content](https://developer.mozilla.org/en-US/docs/Glossary/Block-level_content) 46. [Boolean](https://developer.mozilla.org/en-US/docs/Glossary/Boolean) 1. [Boolean (JavaScript)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/JavaScript) 2. [Boolean attribute (ARIA)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/ARIA) 3. [Boolean attribute (HTML)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/HTML) 47. [Bounding box](https://developer.mozilla.org/en-US/docs/Glossary/Bounding_box) 48. [Breadcrumb](https://developer.mozilla.org/en-US/docs/Glossary/Breadcrumb) 49. [Brotli


id: voip-glossary-mdn-20260505-0
file: data/developer.mozilla.org/en-US/docs/Glossary/VoIP-0.md
category: reference
title: VoIP - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/VoIP
date_saved: 2026-05-05T05:48:36.691190+00:00
instance: kb-cron
parent: voip-glossary-mdn-20260505-0
summary:
* [Skip to main content](https://developer.mozilla.org/en-US/docs/Glossary/VoIP#content) * [Skip to search](https://developer.mozilla.org/en-US/docs/Glossary/VoIP#search) [ MDN ](https://developer.mozilla.org/en-US/) HTML [HTML: Markup language](https://developer.mozilla.org/en-US/docs/Web/HTML) HTML reference * [Elements](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements) * [Global attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes) * [Attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Attributes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference "See all HTML references") HTML guides * [Responsive images](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Responsive_images) * [HTML cheatsheet](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Cheatsheet) * [Date & time formats](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Date_and_time_formats) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides "See all HTML guides") Markup languages * [SVG](https://developer.mozilla.org/en-US/docs/Web/SVG) * [MathML](https://developer.mozilla.org/en-US/docs/Web/MathML) * [XML](https://developer.mozilla.org/en-US/docs/Web/XML) CSS [CSS: Styling language](https://developer.mozilla.org/en-US/docs/Web/CSS) CSS reference * [Properties](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties) * [Selectors](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors) * [At-rules](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/At-rules) * [Values](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference "See all CSS references") CSS guides * [Box model](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Box_model/Introduction) * [Animations](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Animations/Using) * [Flexbox](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Flexible_box_layout/Basic_concepts) * [Colors](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Colors/Applying_color) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides "See all CSS guides") Layout cookbook * [Column layouts](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Column_layouts) * [Centering an element](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Center_an_element) * [Card component](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Card) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook) JavaScriptJS [JavaScript: Scripting language](https://developer.mozilla.org/en-US/docs/Web/JavaScript) JS reference * [Standard built-in objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects) * [Expressions & operators](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators) * [Statements & declarations](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements) * [Functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference "See all JavaScript references") JS guides * [Control flow & error handing](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Control_flow_and_error_handling) * [Loops and iteration](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration) * [Working with objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_objects) * [Using classes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_classes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide "See all JavaScript guides") Web APIs [Web APIs: Programming interfaces](https://developer.mozilla.org/en-US/docs/Web/API) Web API reference * [File system API](https://developer.mozilla.org/en-US/docs/Web/API/File_System_API) * [Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) * [Geolocation API](https://developer.mozilla.org/en-US/docs/Web/API/Geolocation_API) * [HTML DOM API](https://developer.mozilla.org/en-US/docs/Web/API/HTML_DOM_API) * [Push API](https://developer.mozilla.org/en-US/docs/Web/API/Push_API) * [Service worker API](https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API) * [See all…](https://developer.mozilla.org/en-US/docs/Web/API


id: voip-glossary-mdn-20260505-1
file: data/developer.mozilla.org/en-US/docs/Glossary/VoIP-1.md
category: reference
title: VoIP - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/VoIP
date_saved: 2026-05-05T05:48:36.691190+00:00
instance: kb-cron
parent: voip-glossary-mdn-20260505-0
summary:
## Help improve MDN [Learn how to contribute](https://developer.mozilla.org/en-US/docs/MDN/Community/Getting_started) This page was last modified on Jul 11, 2025 by [MDN contributors](https://developer.mozilla.org/en-US/docs/Glossary/VoIP/contributors.txt). [View this page on GitHub](https://github.com/mdn/content/blob/main/files/en-us/glossary/voip/index.md?plain=1 "Folder: en-us/glossary/voip \(Opens in a new tab\)") • [Report a problem with this content](https://github.com/mdn/content/issues/new?template=page-report.yml&mdn-url=https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FVoIP&metadata=%3C%21--+Do+not+make+changes+below+this+line+--%3E%0A%3Cdetails%3E%0A%3Csummary%3EPage+report+details%3C%2Fsummary%3E%0A%0A*+Folder%3A+%60en-us%2Fglossary%2Fvoip%60%0A*+MDN+URL%3A+https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FVoIP%0A*+GitHub+URL%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fblob%2Fmain%2Ffiles%2Fen-us%2Fglossary%2Fvoip%2Findex.md%0A*+Last+commit%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fcommit%2F2547f622337d6cbf8c3794776b17ed377d6aad57%0A*+Document+last+modified%3A+2025-07-11T14%3A45%3A59.000Z%0A%0A%3C%2Fdetails%3E "This will take you to GitHub to file a new issue.") 1. [Glossary](https://developer.mozilla.org/en-US/docs/Glossary) 2. 1. [Abstraction](https://developer.mozilla.org/en-US/docs/Glossary/Abstraction) 2. [Accent](https://developer.mozilla.org/en-US/docs/Glossary/Accent) 3. [Accessibility](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility) 4. [Accessibility tree](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility_tree) 5. [Accessible description](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_description) 6. [Accessible name](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_name) 7. [Adobe Flash](https://developer.mozilla.org/en-US/docs/Glossary/Adobe_Flash) 8. [Advance measure](https://developer.mozilla.org/en-US/docs/Glossary/Advance_measure) 9. [Ajax](https://developer.mozilla.org/en-US/docs/Glossary/AJAX) 10. [Algorithm](https://developer.mozilla.org/en-US/docs/Glossary/Algorithm) 11. [Alignment container](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Container) 12. [Alignment subject](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Subject) 13. [Alpha (alpha channel)](https://developer.mozilla.org/en-US/docs/Glossary/Alpha) 14. [ALPN](https://developer.mozilla.org/en-US/docs/Glossary/ALPN) 15. [API](https://developer.mozilla.org/en-US/docs/Glossary/API) 16. [Apple Safari](https://developer.mozilla.org/en-US/docs/Glossary/Apple_Safari) 17. [Application context](https://developer.mozilla.org/en-US/docs/Glossary/Application_context) 18. [Argument](https://developer.mozilla.org/en-US/docs/Glossary/Argument) 19. [ARIA](https://developer.mozilla.org/en-US/docs/Glossary/ARIA) 20. [ARPA](https://developer.mozilla.org/en-US/docs/Glossary/ARPA) 21. [ARPANET](https://developer.mozilla.org/en-US/docs/Glossary/Arpanet) 22. [Array](https://developer.mozilla.org/en-US/docs/Glossary/Array) 23. [ASCII](https://developer.mozilla.org/en-US/docs/Glossary/ASCII) 24. [Aspect ratio](https://developer.mozilla.org/en-US/docs/Glossary/Aspect_ratio) 25. [Asynchronous](https://developer.mozilla.org/en-US/docs/Glossary/Asynchronous) 26. [ATAG](https://developer.mozilla.org/en-US/docs/Glossary/ATAG) 27. [Attribute](https://developer.mozilla.org/en-US/docs/Glossary/Attribute) 28. [Authentication](https://developer.mozilla.org/en-US/docs/Glossary/Authentication) 29. [Authenticator](https://developer.mozilla.org/en-US/docs/Glossary/Authenticator) 30. [Bandwidth](https://developer.mozilla.org/en-US/docs/Glossary/Bandwidth) 31. [Base64](https://developer.mozilla.org/en-US/docs/Glossary/Base64) 32. [Baseline](https://developer.mozilla.org/en-US/docs/Glossary/Baseline) 1. [Baseline (compatibility)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Compatibility) 2. [Baseline (typography)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Typography) 33. [BCP 47 language tag](https://developer.mozilla.org/en-US/docs/Glossary/BCP_47_language_tag) 34. [Beacon](https://developer.mozilla.org/en-US/docs/Glossary/Beacon) 35. [Bézier curve](https://developer.mozilla.org/en-US/docs/Glossary/Bezier_curve) 36. [bfcache](https://developer.mozilla.org/en-US/docs/Glossary/bfcache) 37. [BiDi](https://developer.mozilla.org/en-US/docs/Glossary/BiDi) 38. [BigInt](https://developer.mozilla.org/en-US/docs/Glossary/BigInt) 39. [Binding](https://developer.mozilla.org/en-US/docs/Glossary/Binding) 40. [Bitwise flags](https://developer.mozilla.org/en-US/docs/Glossary/Bitwise_flags) 41. [Blink](https://developer.mozilla.org/en-US/docs/Glossary/Blink) 42. [blink element (<blink> tag)](https://developer.mozilla.org/en-US/docs/Glossary/blink_element) 43. [Block](https://developer.mozilla.org/en-US/docs/Glossary/Block) 1. [Block (CSS)](https://developer.mozilla.org/en-US/docs/Glossary/Block/CSS) 2. [Block (scripting)](https://developer.mozilla.org/en-US/docs/Glossary/Block/Scripting) 44. [Block cipher mode of operation](https://developer.mozilla.org/en-US/docs/Glossary/Block_cipher_mode_of_operation) 45. [Block-level content](https://developer.mozilla.org/en-US/docs/Glossary/Block-level_content) 46. [Boolean](https://developer.mozilla.org/en-US/docs/Glossary/Boolean) 1. [Boolean (JavaScript)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/JavaScript) 2. [Boolean attribute (ARIA)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/ARIA) 3. [Boolean attribute (HTML)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/HTML) 47. [Bounding box](https://developer.mozilla.org/en-US/docs/Glossary/Bounding_box) 48. [Breadcrumb](https://developer.mozilla.org/en-US/docs/Glossary/Breadcrumb) 49. [Brotli


id: void-element-glossary-mdn-20260505-0
file: data/developer.mozilla.org/en-US/docs/Glossary/Void_element-0.md
category: reference
title: Void element - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/Void_element
date_saved: 2026-05-05T05:48:39.015862+00:00
instance: kb-cron
parent: void-element-glossary-mdn-20260505-0
summary:
* [Skip to main content](https://developer.mozilla.org/en-US/docs/Glossary/Void_element#content) * [Skip to search](https://developer.mozilla.org/en-US/docs/Glossary/Void_element#search) [ MDN ](https://developer.mozilla.org/en-US/) HTML [HTML: Markup language](https://developer.mozilla.org/en-US/docs/Web/HTML) HTML reference * [Elements](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements) * [Global attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes) * [Attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Attributes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference "See all HTML references") HTML guides * [Responsive images](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Responsive_images) * [HTML cheatsheet](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Cheatsheet) * [Date & time formats](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Date_and_time_formats) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides "See all HTML guides") Markup languages * [SVG](https://developer.mozilla.org/en-US/docs/Web/SVG) * [MathML](https://developer.mozilla.org/en-US/docs/Web/MathML) * [XML](https://developer.mozilla.org/en-US/docs/Web/XML) CSS [CSS: Styling language](https://developer.mozilla.org/en-US/docs/Web/CSS) CSS reference * [Properties](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties) * [Selectors](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors) * [At-rules](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/At-rules) * [Values](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference "See all CSS references") CSS guides * [Box model](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Box_model/Introduction) * [Animations](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Animations/Using) * [Flexbox](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Flexible_box_layout/Basic_concepts) * [Colors](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Colors/Applying_color) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides "See all CSS guides") Layout cookbook * [Column layouts](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Column_layouts) * [Centering an element](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Center_an_element) * [Card component](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Card) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook) JavaScriptJS [JavaScript: Scripting language](https://developer.mozilla.org/en-US/docs/Web/JavaScript) JS reference * [Standard built-in objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects) * [Expressions & operators](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators) * [Statements & declarations](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements) * [Functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference "See all JavaScript references") JS guides * [Control flow & error handing](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Control_flow_and_error_handling) * [Loops and iteration](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration) * [Working with objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_objects) * [Using classes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_classes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide "See all JavaScript guides") Web APIs [Web APIs: Programming interfaces](https://developer.mozilla.org/en-US/docs/Web/API) Web API reference * [File system API](https://developer.mozilla.org/en-US/docs/Web/API/File_System_API) * [Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) * [Geolocation API](https://developer.mozilla.org/en-US/docs/Web/API/Geolocation_API) * [HTML DOM API](https://developer.mozilla.org/en-US/docs/Web/API/HTML_DOM_API) * [Push API](https://developer.mozilla.org/en-US/docs/Web/API/Push_API) * [Service worker API](https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API) * [See all…](https://developer.mozilla.org/en-US/docs/Web/API


id: void-element-glossary-mdn-20260505-1
file: data/developer.mozilla.org/en-US/docs/Glossary/Void_element-1.md
category: reference
title: Void element - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/Void_element
date_saved: 2026-05-05T05:48:39.015862+00:00
instance: kb-cron
parent: void-element-glossary-mdn-20260505-0
summary:
## Help improve MDN [Learn how to contribute](https://developer.mozilla.org/en-US/docs/MDN/Community/Getting_started) This page was last modified on Apr 7, 2026 by [MDN contributors](https://developer.mozilla.org/en-US/docs/Glossary/Void_element/contributors.txt). [View this page on GitHub](https://github.com/mdn/content/blob/main/files/en-us/glossary/void_element/index.md?plain=1 "Folder: en-us/glossary/void_element \(Opens in a new tab\)") • [Report a problem with this content](https://github.com/mdn/content/issues/new?template=page-report.yml&mdn-url=https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FVoid_element&metadata=%3C%21--+Do+not+make+changes+below+this+line+--%3E%0A%3Cdetails%3E%0A%3Csummary%3EPage+report+details%3C%2Fsummary%3E%0A%0A*+Folder%3A+%60en-us%2Fglossary%2Fvoid_element%60%0A*+MDN+URL%3A+https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FVoid_element%0A*+GitHub+URL%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fblob%2Fmain%2Ffiles%2Fen-us%2Fglossary%2Fvoid_element%2Findex.md%0A*+Last+commit%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fcommit%2Fd559e66723de93ce6c59eb5d22a29afca7265c2a%0A*+Document+last+modified%3A+2026-04-07T16%3A49%3A20.000Z%0A%0A%3C%2Fdetails%3E "This will take you to GitHub to file a new issue.") 1. [Glossary](https://developer.mozilla.org/en-US/docs/Glossary) 2. 1. [Abstraction](https://developer.mozilla.org/en-US/docs/Glossary/Abstraction) 2. [Accent](https://developer.mozilla.org/en-US/docs/Glossary/Accent) 3. [Accessibility](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility) 4. [Accessibility tree](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility_tree) 5. [Accessible description](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_description) 6. [Accessible name](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_name) 7. [Adobe Flash](https://developer.mozilla.org/en-US/docs/Glossary/Adobe_Flash) 8. [Advance measure](https://developer.mozilla.org/en-US/docs/Glossary/Advance_measure) 9. [Ajax](https://developer.mozilla.org/en-US/docs/Glossary/AJAX) 10. [Algorithm](https://developer.mozilla.org/en-US/docs/Glossary/Algorithm) 11. [Alignment container](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Container) 12. [Alignment subject](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Subject) 13. [Alpha (alpha channel)](https://developer.mozilla.org/en-US/docs/Glossary/Alpha) 14. [ALPN](https://developer.mozilla.org/en-US/docs/Glossary/ALPN) 15. [API](https://developer.mozilla.org/en-US/docs/Glossary/API) 16. [Apple Safari](https://developer.mozilla.org/en-US/docs/Glossary/Apple_Safari) 17. [Application context](https://developer.mozilla.org/en-US/docs/Glossary/Application_context) 18. [Argument](https://developer.mozilla.org/en-US/docs/Glossary/Argument) 19. [ARIA](https://developer.mozilla.org/en-US/docs/Glossary/ARIA) 20. [ARPA](https://developer.mozilla.org/en-US/docs/Glossary/ARPA) 21. [ARPANET](https://developer.mozilla.org/en-US/docs/Glossary/Arpanet) 22. [Array](https://developer.mozilla.org/en-US/docs/Glossary/Array) 23. [ASCII](https://developer.mozilla.org/en-US/docs/Glossary/ASCII) 24. [Aspect ratio](https://developer.mozilla.org/en-US/docs/Glossary/Aspect_ratio) 25. [Asynchronous](https://developer.mozilla.org/en-US/docs/Glossary/Asynchronous) 26. [ATAG](https://developer.mozilla.org/en-US/docs/Glossary/ATAG) 27. [Attribute](https://developer.mozilla.org/en-US/docs/Glossary/Attribute) 28. [Authentication](https://developer.mozilla.org/en-US/docs/Glossary/Authentication) 29. [Authenticator](https://developer.mozilla.org/en-US/docs/Glossary/Authenticator) 30. [Bandwidth](https://developer.mozilla.org/en-US/docs/Glossary/Bandwidth) 31. [Base64](https://developer.mozilla.org/en-US/docs/Glossary/Base64) 32. [Baseline](https://developer.mozilla.org/en-US/docs/Glossary/Baseline) 1. [Baseline (compatibility)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Compatibility) 2. [Baseline (typography)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Typography) 33. [BCP 47 language tag](https://developer.mozilla.org/en-US/docs/Glossary/BCP_47_language_tag) 34. [Beacon](https://developer.mozilla.org/en-US/docs/Glossary/Beacon) 35. [Bézier curve](https://developer.mozilla.org/en-US/docs/Glossary/Bezier_curve) 36. [bfcache](https://developer.mozilla.org/en-US/docs/Glossary/bfcache) 37. [BiDi](https://developer.mozilla.org/en-US/docs/Glossary/BiDi) 38. [BigInt](https://developer.mozilla.org/en-US/docs/Glossary/BigInt) 39. [Binding](https://developer.mozilla.org/en-US/docs/Glossary/Binding) 40. [Bitwise flags](https://developer.mozilla.org/en-US/docs/Glossary/Bitwise_flags) 41. [Blink](https://developer.mozilla.org/en-US/docs/Glossary/Blink) 42. [blink element (<blink> tag)](https://developer.mozilla.org/en-US/docs/Glossary/blink_element) 43. [Block](https://developer.mozilla.org/en-US/docs/Glossary/Block) 1. [Block (CSS)](https://developer.mozilla.org/en-US/docs/Glossary/Block/CSS) 2. [Block (scripting)](https://developer.mozilla.org/en-US/docs/Glossary/Block/Scripting) 44. [Block cipher mode of operation](https://developer.mozilla.org/en-US/docs/Glossary/Block_cipher_mode_of_operation) 45. [Block-level content](https://developer.mozilla.org/en-US/docs/Glossary/Block-level_content) 46. [Boolean](https://developer.mozilla.org/en-US/docs/Glossary/Boolean) 1. [Boolean (JavaScript)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/JavaScript) 2. [Boolean attribute (ARIA)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/ARIA) 3. [Boolean attribute (HTML)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/HTML) 47. [Bounding box](https://developer.mozilla.org/en-US/docs/Glossary/Bounding_box) 48. [Breadcrumb](https://developer.mozilla.org/en-US/docs/Glossary/Breadcrumb) 49. [Brotli


id: w3c-glossary-mdn-20260505-0
file: data/developer.mozilla.org/en-US/docs/Glossary/W3C-0.md
category: reference
title: W3C - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/W3C
date_saved: 2026-05-05T05:48:41.729535+00:00
instance: kb-cron
parent: w3c-glossary-mdn-20260505-0
summary:
* [Skip to main content](https://developer.mozilla.org/en-US/docs/Glossary/W3C#content) * [Skip to search](https://developer.mozilla.org/en-US/docs/Glossary/W3C#search) [ MDN ](https://developer.mozilla.org/en-US/) HTML [HTML: Markup language](https://developer.mozilla.org/en-US/docs/Web/HTML) HTML reference * [Elements](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements) * [Global attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes) * [Attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Attributes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference "See all HTML references") HTML guides * [Responsive images](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Responsive_images) * [HTML cheatsheet](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Cheatsheet) * [Date & time formats](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Date_and_time_formats) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides "See all HTML guides") Markup languages * [SVG](https://developer.mozilla.org/en-US/docs/Web/SVG) * [MathML](https://developer.mozilla.org/en-US/docs/Web/MathML) * [XML](https://developer.mozilla.org/en-US/docs/Web/XML) CSS [CSS: Styling language](https://developer.mozilla.org/en-US/docs/Web/CSS) CSS reference * [Properties](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties) * [Selectors](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors) * [At-rules](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/At-rules) * [Values](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference "See all CSS references") CSS guides * [Box model](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Box_model/Introduction) * [Animations](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Animations/Using) * [Flexbox](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Flexible_box_layout/Basic_concepts) * [Colors](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Colors/Applying_color) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides "See all CSS guides") Layout cookbook * [Column layouts](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Column_layouts) * [Centering an element](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Center_an_element) * [Card component](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Card) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook) JavaScriptJS [JavaScript: Scripting language](https://developer.mozilla.org/en-US/docs/Web/JavaScript) JS reference * [Standard built-in objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects) * [Expressions & operators](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators) * [Statements & declarations](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements) * [Functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference "See all JavaScript references") JS guides * [Control flow & error handing](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Control_flow_and_error_handling) * [Loops and iteration](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration) * [Working with objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_objects) * [Using classes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_classes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide "See all JavaScript guides") Web APIs [Web APIs: Programming interfaces](https://developer.mozilla.org/en-US/docs/Web/API) Web API reference * [File system API](https://developer.mozilla.org/en-US/docs/Web/API/File_System_API) * [Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) * [Geolocation API](https://developer.mozilla.org/en-US/docs/Web/API/Geolocation_API) * [HTML DOM API](https://developer.mozilla.org/en-US/docs/Web/API/HTML_DOM_API) * [Push API](https://developer.mozilla.org/en-US/docs/Web/API/Push_API) * [Service worker API](https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API) * [See all…](https://developer.mozilla.org/en-US/docs/Web/API


id: w3c-glossary-mdn-20260505-1
file: data/developer.mozilla.org/en-US/docs/Glossary/W3C-1.md
category: reference
title: W3C - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/W3C
date_saved: 2026-05-05T05:48:41.729535+00:00
instance: kb-cron
parent: w3c-glossary-mdn-20260505-0
summary:
## Help improve MDN [Learn how to contribute](https://developer.mozilla.org/en-US/docs/MDN/Community/Getting_started) This page was last modified on Jul 11, 2025 by [MDN contributors](https://developer.mozilla.org/en-US/docs/Glossary/W3C/contributors.txt). [View this page on GitHub](https://github.com/mdn/content/blob/main/files/en-us/glossary/w3c/index.md?plain=1 "Folder: en-us/glossary/w3c \(Opens in a new tab\)") • [Report a problem with this content](https://github.com/mdn/content/issues/new?template=page-report.yml&mdn-url=https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FW3C&metadata=%3C%21--+Do+not+make+changes+below+this+line+--%3E%0A%3Cdetails%3E%0A%3Csummary%3EPage+report+details%3C%2Fsummary%3E%0A%0A*+Folder%3A+%60en-us%2Fglossary%2Fw3c%60%0A*+MDN+URL%3A+https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FW3C%0A*+GitHub+URL%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fblob%2Fmain%2Ffiles%2Fen-us%2Fglossary%2Fw3c%2Findex.md%0A*+Last+commit%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fcommit%2F2547f622337d6cbf8c3794776b17ed377d6aad57%0A*+Document+last+modified%3A+2025-07-11T14%3A45%3A59.000Z%0A%0A%3C%2Fdetails%3E "This will take you to GitHub to file a new issue.") 1. [Glossary](https://developer.mozilla.org/en-US/docs/Glossary) 2. 1. [Abstraction](https://developer.mozilla.org/en-US/docs/Glossary/Abstraction) 2. [Accent](https://developer.mozilla.org/en-US/docs/Glossary/Accent) 3. [Accessibility](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility) 4. [Accessibility tree](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility_tree) 5. [Accessible description](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_description) 6. [Accessible name](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_name) 7. [Adobe Flash](https://developer.mozilla.org/en-US/docs/Glossary/Adobe_Flash) 8. [Advance measure](https://developer.mozilla.org/en-US/docs/Glossary/Advance_measure) 9. [Ajax](https://developer.mozilla.org/en-US/docs/Glossary/AJAX) 10. [Algorithm](https://developer.mozilla.org/en-US/docs/Glossary/Algorithm) 11. [Alignment container](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Container) 12. [Alignment subject](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Subject) 13. [Alpha (alpha channel)](https://developer.mozilla.org/en-US/docs/Glossary/Alpha) 14. [ALPN](https://developer.mozilla.org/en-US/docs/Glossary/ALPN) 15. [API](https://developer.mozilla.org/en-US/docs/Glossary/API) 16. [Apple Safari](https://developer.mozilla.org/en-US/docs/Glossary/Apple_Safari) 17. [Application context](https://developer.mozilla.org/en-US/docs/Glossary/Application_context) 18. [Argument](https://developer.mozilla.org/en-US/docs/Glossary/Argument) 19. [ARIA](https://developer.mozilla.org/en-US/docs/Glossary/ARIA) 20. [ARPA](https://developer.mozilla.org/en-US/docs/Glossary/ARPA) 21. [ARPANET](https://developer.mozilla.org/en-US/docs/Glossary/Arpanet) 22. [Array](https://developer.mozilla.org/en-US/docs/Glossary/Array) 23. [ASCII](https://developer.mozilla.org/en-US/docs/Glossary/ASCII) 24. [Aspect ratio](https://developer.mozilla.org/en-US/docs/Glossary/Aspect_ratio) 25. [Asynchronous](https://developer.mozilla.org/en-US/docs/Glossary/Asynchronous) 26. [ATAG](https://developer.mozilla.org/en-US/docs/Glossary/ATAG) 27. [Attribute](https://developer.mozilla.org/en-US/docs/Glossary/Attribute) 28. [Authentication](https://developer.mozilla.org/en-US/docs/Glossary/Authentication) 29. [Authenticator](https://developer.mozilla.org/en-US/docs/Glossary/Authenticator) 30. [Bandwidth](https://developer.mozilla.org/en-US/docs/Glossary/Bandwidth) 31. [Base64](https://developer.mozilla.org/en-US/docs/Glossary/Base64) 32. [Baseline](https://developer.mozilla.org/en-US/docs/Glossary/Baseline) 1. [Baseline (compatibility)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Compatibility) 2. [Baseline (typography)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Typography) 33. [BCP 47 language tag](https://developer.mozilla.org/en-US/docs/Glossary/BCP_47_language_tag) 34. [Beacon](https://developer.mozilla.org/en-US/docs/Glossary/Beacon) 35. [Bézier curve](https://developer.mozilla.org/en-US/docs/Glossary/Bezier_curve) 36. [bfcache](https://developer.mozilla.org/en-US/docs/Glossary/bfcache) 37. [BiDi](https://developer.mozilla.org/en-US/docs/Glossary/BiDi) 38. [BigInt](https://developer.mozilla.org/en-US/docs/Glossary/BigInt) 39. [Binding](https://developer.mozilla.org/en-US/docs/Glossary/Binding) 40. [Bitwise flags](https://developer.mozilla.org/en-US/docs/Glossary/Bitwise_flags) 41. [Blink](https://developer.mozilla.org/en-US/docs/Glossary/Blink) 42. [blink element (<blink> tag)](https://developer.mozilla.org/en-US/docs/Glossary/blink_element) 43. [Block](https://developer.mozilla.org/en-US/docs/Glossary/Block) 1. [Block (CSS)](https://developer.mozilla.org/en-US/docs/Glossary/Block/CSS) 2. [Block (scripting)](https://developer.mozilla.org/en-US/docs/Glossary/Block/Scripting) 44. [Block cipher mode of operation](https://developer.mozilla.org/en-US/docs/Glossary/Block_cipher_mode_of_operation) 45. [Block-level content](https://developer.mozilla.org/en-US/docs/Glossary/Block-level_content) 46. [Boolean](https://developer.mozilla.org/en-US/docs/Glossary/Boolean) 1. [Boolean (JavaScript)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/JavaScript) 2. [Boolean attribute (ARIA)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/ARIA) 3. [Boolean attribute (HTML)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/HTML) 47. [Bounding box](https://developer.mozilla.org/en-US/docs/Glossary/Bounding_box) 48. [Breadcrumb](https://developer.mozilla.org/en-US/docs/Glossary/Breadcrumb) 49. [Brotli


id: wai-glossary-mdn-20260505-0
file: data/developer.mozilla.org/en-US/docs/Glossary/WAI-0.md
category: reference
title: WAI - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/WAI
date_saved: 2026-05-05T05:48:44.282653+00:00
instance: kb-cron
parent: wai-glossary-mdn-20260505-0
summary:
* [Skip to main content](https://developer.mozilla.org/en-US/docs/Glossary/WAI#content) * [Skip to search](https://developer.mozilla.org/en-US/docs/Glossary/WAI#search) [ MDN ](https://developer.mozilla.org/en-US/) HTML [HTML: Markup language](https://developer.mozilla.org/en-US/docs/Web/HTML) HTML reference * [Elements](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements) * [Global attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes) * [Attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Attributes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference "See all HTML references") HTML guides * [Responsive images](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Responsive_images) * [HTML cheatsheet](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Cheatsheet) * [Date & time formats](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Date_and_time_formats) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides "See all HTML guides") Markup languages * [SVG](https://developer.mozilla.org/en-US/docs/Web/SVG) * [MathML](https://developer.mozilla.org/en-US/docs/Web/MathML) * [XML](https://developer.mozilla.org/en-US/docs/Web/XML) CSS [CSS: Styling language](https://developer.mozilla.org/en-US/docs/Web/CSS) CSS reference * [Properties](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties) * [Selectors](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors) * [At-rules](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/At-rules) * [Values](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference "See all CSS references") CSS guides * [Box model](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Box_model/Introduction) * [Animations](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Animations/Using) * [Flexbox](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Flexible_box_layout/Basic_concepts) * [Colors](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Colors/Applying_color) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides "See all CSS guides") Layout cookbook * [Column layouts](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Column_layouts) * [Centering an element](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Center_an_element) * [Card component](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Card) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook) JavaScriptJS [JavaScript: Scripting language](https://developer.mozilla.org/en-US/docs/Web/JavaScript) JS reference * [Standard built-in objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects) * [Expressions & operators](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators) * [Statements & declarations](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements) * [Functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference "See all JavaScript references") JS guides * [Control flow & error handing](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Control_flow_and_error_handling) * [Loops and iteration](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration) * [Working with objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_objects) * [Using classes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_classes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide "See all JavaScript guides") Web APIs [Web APIs: Programming interfaces](https://developer.mozilla.org/en-US/docs/Web/API) Web API reference * [File system API](https://developer.mozilla.org/en-US/docs/Web/API/File_System_API) * [Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) * [Geolocation API](https://developer.mozilla.org/en-US/docs/Web/API/Geolocation_API) * [HTML DOM API](https://developer.mozilla.org/en-US/docs/Web/API/HTML_DOM_API) * [Push API](https://developer.mozilla.org/en-US/docs/Web/API/Push_API) * [Service worker API](https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API) * [See all…](https://developer.mozilla.org/en-US/docs/Web/API


id: wai-glossary-mdn-20260505-1
file: data/developer.mozilla.org/en-US/docs/Glossary/WAI-1.md
category: reference
title: WAI - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/WAI
date_saved: 2026-05-05T05:48:44.282653+00:00
instance: kb-cron
parent: wai-glossary-mdn-20260505-0
summary:
## Help improve MDN [Learn how to contribute](https://developer.mozilla.org/en-US/docs/MDN/Community/Getting_started) This page was last modified on Jul 11, 2025 by [MDN contributors](https://developer.mozilla.org/en-US/docs/Glossary/WAI/contributors.txt). [View this page on GitHub](https://github.com/mdn/content/blob/main/files/en-us/glossary/wai/index.md?plain=1 "Folder: en-us/glossary/wai \(Opens in a new tab\)") • [Report a problem with this content](https://github.com/mdn/content/issues/new?template=page-report.yml&mdn-url=https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FWAI&metadata=%3C%21--+Do+not+make+changes+below+this+line+--%3E%0A%3Cdetails%3E%0A%3Csummary%3EPage+report+details%3C%2Fsummary%3E%0A%0A*+Folder%3A+%60en-us%2Fglossary%2Fwai%60%0A*+MDN+URL%3A+https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FWAI%0A*+GitHub+URL%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fblob%2Fmain%2Ffiles%2Fen-us%2Fglossary%2Fwai%2Findex.md%0A*+Last+commit%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fcommit%2F2547f622337d6cbf8c3794776b17ed377d6aad57%0A*+Document+last+modified%3A+2025-07-11T14%3A45%3A59.000Z%0A%0A%3C%2Fdetails%3E "This will take you to GitHub to file a new issue.") 1. [Glossary](https://developer.mozilla.org/en-US/docs/Glossary) 2. 1. [Abstraction](https://developer.mozilla.org/en-US/docs/Glossary/Abstraction) 2. [Accent](https://developer.mozilla.org/en-US/docs/Glossary/Accent) 3. [Accessibility](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility) 4. [Accessibility tree](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility_tree) 5. [Accessible description](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_description) 6. [Accessible name](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_name) 7. [Adobe Flash](https://developer.mozilla.org/en-US/docs/Glossary/Adobe_Flash) 8. [Advance measure](https://developer.mozilla.org/en-US/docs/Glossary/Advance_measure) 9. [Ajax](https://developer.mozilla.org/en-US/docs/Glossary/AJAX) 10. [Algorithm](https://developer.mozilla.org/en-US/docs/Glossary/Algorithm) 11. [Alignment container](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Container) 12. [Alignment subject](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Subject) 13. [Alpha (alpha channel)](https://developer.mozilla.org/en-US/docs/Glossary/Alpha) 14. [ALPN](https://developer.mozilla.org/en-US/docs/Glossary/ALPN) 15. [API](https://developer.mozilla.org/en-US/docs/Glossary/API) 16. [Apple Safari](https://developer.mozilla.org/en-US/docs/Glossary/Apple_Safari) 17. [Application context](https://developer.mozilla.org/en-US/docs/Glossary/Application_context) 18. [Argument](https://developer.mozilla.org/en-US/docs/Glossary/Argument) 19. [ARIA](https://developer.mozilla.org/en-US/docs/Glossary/ARIA) 20. [ARPA](https://developer.mozilla.org/en-US/docs/Glossary/ARPA) 21. [ARPANET](https://developer.mozilla.org/en-US/docs/Glossary/Arpanet) 22. [Array](https://developer.mozilla.org/en-US/docs/Glossary/Array) 23. [ASCII](https://developer.mozilla.org/en-US/docs/Glossary/ASCII) 24. [Aspect ratio](https://developer.mozilla.org/en-US/docs/Glossary/Aspect_ratio) 25. [Asynchronous](https://developer.mozilla.org/en-US/docs/Glossary/Asynchronous) 26. [ATAG](https://developer.mozilla.org/en-US/docs/Glossary/ATAG) 27. [Attribute](https://developer.mozilla.org/en-US/docs/Glossary/Attribute) 28. [Authentication](https://developer.mozilla.org/en-US/docs/Glossary/Authentication) 29. [Authenticator](https://developer.mozilla.org/en-US/docs/Glossary/Authenticator) 30. [Bandwidth](https://developer.mozilla.org/en-US/docs/Glossary/Bandwidth) 31. [Base64](https://developer.mozilla.org/en-US/docs/Glossary/Base64) 32. [Baseline](https://developer.mozilla.org/en-US/docs/Glossary/Baseline) 1. [Baseline (compatibility)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Compatibility) 2. [Baseline (typography)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Typography) 33. [BCP 47 language tag](https://developer.mozilla.org/en-US/docs/Glossary/BCP_47_language_tag) 34. [Beacon](https://developer.mozilla.org/en-US/docs/Glossary/Beacon) 35. [Bézier curve](https://developer.mozilla.org/en-US/docs/Glossary/Bezier_curve) 36. [bfcache](https://developer.mozilla.org/en-US/docs/Glossary/bfcache) 37. [BiDi](https://developer.mozilla.org/en-US/docs/Glossary/BiDi) 38. [BigInt](https://developer.mozilla.org/en-US/docs/Glossary/BigInt) 39. [Binding](https://developer.mozilla.org/en-US/docs/Glossary/Binding) 40. [Bitwise flags](https://developer.mozilla.org/en-US/docs/Glossary/Bitwise_flags) 41. [Blink](https://developer.mozilla.org/en-US/docs/Glossary/Blink) 42. [blink element (<blink> tag)](https://developer.mozilla.org/en-US/docs/Glossary/blink_element) 43. [Block](https://developer.mozilla.org/en-US/docs/Glossary/Block) 1. [Block (CSS)](https://developer.mozilla.org/en-US/docs/Glossary/Block/CSS) 2. [Block (scripting)](https://developer.mozilla.org/en-US/docs/Glossary/Block/Scripting) 44. [Block cipher mode of operation](https://developer.mozilla.org/en-US/docs/Glossary/Block_cipher_mode_of_operation) 45. [Block-level content](https://developer.mozilla.org/en-US/docs/Glossary/Block-level_content) 46. [Boolean](https://developer.mozilla.org/en-US/docs/Glossary/Boolean) 1. [Boolean (JavaScript)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/JavaScript) 2. [Boolean attribute (ARIA)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/ARIA) 3. [Boolean attribute (HTML)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/HTML) 47. [Bounding box](https://developer.mozilla.org/en-US/docs/Glossary/Bounding_box) 48. [Breadcrumb](https://developer.mozilla.org/en-US/docs/Glossary/Breadcrumb) 49. [Brotli


id: wcag-glossary-mdn-20260505-0
file: data/developer.mozilla.org/en-US/docs/Glossary/WCAG-0.md
category: reference
title: WCAG - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/WCAG
date_saved: 2026-05-05T05:48:46.787158+00:00
instance: kb-cron
parent: wcag-glossary-mdn-20260505-0
summary:
* [Skip to main content](https://developer.mozilla.org/en-US/docs/Glossary/WCAG#content) * [Skip to search](https://developer.mozilla.org/en-US/docs/Glossary/WCAG#search) [ MDN ](https://developer.mozilla.org/en-US/) HTML [HTML: Markup language](https://developer.mozilla.org/en-US/docs/Web/HTML) HTML reference * [Elements](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements) * [Global attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes) * [Attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Attributes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference "See all HTML references") HTML guides * [Responsive images](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Responsive_images) * [HTML cheatsheet](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Cheatsheet) * [Date & time formats](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Date_and_time_formats) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides "See all HTML guides") Markup languages * [SVG](https://developer.mozilla.org/en-US/docs/Web/SVG) * [MathML](https://developer.mozilla.org/en-US/docs/Web/MathML) * [XML](https://developer.mozilla.org/en-US/docs/Web/XML) CSS [CSS: Styling language](https://developer.mozilla.org/en-US/docs/Web/CSS) CSS reference * [Properties](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties) * [Selectors](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors) * [At-rules](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/At-rules) * [Values](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference "See all CSS references") CSS guides * [Box model](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Box_model/Introduction) * [Animations](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Animations/Using) * [Flexbox](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Flexible_box_layout/Basic_concepts) * [Colors](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Colors/Applying_color) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides "See all CSS guides") Layout cookbook * [Column layouts](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Column_layouts) * [Centering an element](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Center_an_element) * [Card component](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Card) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook) JavaScriptJS [JavaScript: Scripting language](https://developer.mozilla.org/en-US/docs/Web/JavaScript) JS reference * [Standard built-in objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects) * [Expressions & operators](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators) * [Statements & declarations](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements) * [Functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference "See all JavaScript references") JS guides * [Control flow & error handing](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Control_flow_and_error_handling) * [Loops and iteration](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration) * [Working with objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_objects) * [Using classes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_classes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide "See all JavaScript guides") Web APIs [Web APIs: Programming interfaces](https://developer.mozilla.org/en-US/docs/Web/API) Web API reference * [File system API](https://developer.mozilla.org/en-US/docs/Web/API/File_System_API) * [Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) * [Geolocation API](https://developer.mozilla.org/en-US/docs/Web/API/Geolocation_API) * [HTML DOM API](https://developer.mozilla.org/en-US/docs/Web/API/HTML_DOM_API) * [Push API](https://developer.mozilla.org/en-US/docs/Web/API/Push_API) * [Service worker API](https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API) * [See all…](https://developer.mozilla.org/en-US/docs/Web/API


id: wcag-glossary-mdn-20260505-1
file: data/developer.mozilla.org/en-US/docs/Glossary/WCAG-1.md
category: reference
title: WCAG - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/WCAG
date_saved: 2026-05-05T05:48:46.787158+00:00
instance: kb-cron
parent: wcag-glossary-mdn-20260505-0
summary:
## Help improve MDN [Learn how to contribute](https://developer.mozilla.org/en-US/docs/MDN/Community/Getting_started) This page was last modified on Jul 11, 2025 by [MDN contributors](https://developer.mozilla.org/en-US/docs/Glossary/WCAG/contributors.txt). [View this page on GitHub](https://github.com/mdn/content/blob/main/files/en-us/glossary/wcag/index.md?plain=1 "Folder: en-us/glossary/wcag \(Opens in a new tab\)") • [Report a problem with this content](https://github.com/mdn/content/issues/new?template=page-report.yml&mdn-url=https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FWCAG&metadata=%3C%21--+Do+not+make+changes+below+this+line+--%3E%0A%3Cdetails%3E%0A%3Csummary%3EPage+report+details%3C%2Fsummary%3E%0A%0A*+Folder%3A+%60en-us%2Fglossary%2Fwcag%60%0A*+MDN+URL%3A+https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FWCAG%0A*+GitHub+URL%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fblob%2Fmain%2Ffiles%2Fen-us%2Fglossary%2Fwcag%2Findex.md%0A*+Last+commit%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fcommit%2F2547f622337d6cbf8c3794776b17ed377d6aad57%0A*+Document+last+modified%3A+2025-07-11T14%3A45%3A59.000Z%0A%0A%3C%2Fdetails%3E "This will take you to GitHub to file a new issue.") 1. [Glossary](https://developer.mozilla.org/en-US/docs/Glossary) 2. 1. [Abstraction](https://developer.mozilla.org/en-US/docs/Glossary/Abstraction) 2. [Accent](https://developer.mozilla.org/en-US/docs/Glossary/Accent) 3. [Accessibility](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility) 4. [Accessibility tree](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility_tree) 5. [Accessible description](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_description) 6. [Accessible name](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_name) 7. [Adobe Flash](https://developer.mozilla.org/en-US/docs/Glossary/Adobe_Flash) 8. [Advance measure](https://developer.mozilla.org/en-US/docs/Glossary/Advance_measure) 9. [Ajax](https://developer.mozilla.org/en-US/docs/Glossary/AJAX) 10. [Algorithm](https://developer.mozilla.org/en-US/docs/Glossary/Algorithm) 11. [Alignment container](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Container) 12. [Alignment subject](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Subject) 13. [Alpha (alpha channel)](https://developer.mozilla.org/en-US/docs/Glossary/Alpha) 14. [ALPN](https://developer.mozilla.org/en-US/docs/Glossary/ALPN) 15. [API](https://developer.mozilla.org/en-US/docs/Glossary/API) 16. [Apple Safari](https://developer.mozilla.org/en-US/docs/Glossary/Apple_Safari) 17. [Application context](https://developer.mozilla.org/en-US/docs/Glossary/Application_context) 18. [Argument](https://developer.mozilla.org/en-US/docs/Glossary/Argument) 19. [ARIA](https://developer.mozilla.org/en-US/docs/Glossary/ARIA) 20. [ARPA](https://developer.mozilla.org/en-US/docs/Glossary/ARPA) 21. [ARPANET](https://developer.mozilla.org/en-US/docs/Glossary/Arpanet) 22. [Array](https://developer.mozilla.org/en-US/docs/Glossary/Array) 23. [ASCII](https://developer.mozilla.org/en-US/docs/Glossary/ASCII) 24. [Aspect ratio](https://developer.mozilla.org/en-US/docs/Glossary/Aspect_ratio) 25. [Asynchronous](https://developer.mozilla.org/en-US/docs/Glossary/Asynchronous) 26. [ATAG](https://developer.mozilla.org/en-US/docs/Glossary/ATAG) 27. [Attribute](https://developer.mozilla.org/en-US/docs/Glossary/Attribute) 28. [Authentication](https://developer.mozilla.org/en-US/docs/Glossary/Authentication) 29. [Authenticator](https://developer.mozilla.org/en-US/docs/Glossary/Authenticator) 30. [Bandwidth](https://developer.mozilla.org/en-US/docs/Glossary/Bandwidth) 31. [Base64](https://developer.mozilla.org/en-US/docs/Glossary/Base64) 32. [Baseline](https://developer.mozilla.org/en-US/docs/Glossary/Baseline) 1. [Baseline (compatibility)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Compatibility) 2. [Baseline (typography)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Typography) 33. [BCP 47 language tag](https://developer.mozilla.org/en-US/docs/Glossary/BCP_47_language_tag) 34. [Beacon](https://developer.mozilla.org/en-US/docs/Glossary/Beacon) 35. [Bézier curve](https://developer.mozilla.org/en-US/docs/Glossary/Bezier_curve) 36. [bfcache](https://developer.mozilla.org/en-US/docs/Glossary/bfcache) 37. [BiDi](https://developer.mozilla.org/en-US/docs/Glossary/BiDi) 38. [BigInt](https://developer.mozilla.org/en-US/docs/Glossary/BigInt) 39. [Binding](https://developer.mozilla.org/en-US/docs/Glossary/Binding) 40. [Bitwise flags](https://developer.mozilla.org/en-US/docs/Glossary/Bitwise_flags) 41. [Blink](https://developer.mozilla.org/en-US/docs/Glossary/Blink) 42. [blink element (<blink> tag)](https://developer.mozilla.org/en-US/docs/Glossary/blink_element) 43. [Block](https://developer.mozilla.org/en-US/docs/Glossary/Block) 1. [Block (CSS)](https://developer.mozilla.org/en-US/docs/Glossary/Block/CSS) 2. [Block (scripting)](https://developer.mozilla.org/en-US/docs/Glossary/Block/Scripting) 44. [Block cipher mode of operation](https://developer.mozilla.org/en-US/docs/Glossary/Block_cipher_mode_of_operation) 45. [Block-level content](https://developer.mozilla.org/en-US/docs/Glossary/Block-level_content) 46. [Boolean](https://developer.mozilla.org/en-US/docs/Glossary/Boolean) 1. [Boolean (JavaScript)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/JavaScript) 2. [Boolean attribute (ARIA)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/ARIA) 3. [Boolean attribute (HTML)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/HTML) 47. [Bounding box](https://developer.mozilla.org/en-US/docs/Glossary/Bounding_box) 48. [Breadcrumb](https://developer.mozilla.org/en-US/docs/Glossary/Breadcrumb) 49. [Brotli


id: whatwg-glossary-mdn-20260505-0
file: data/developer.mozilla.org/en-US/docs/Glossary/WHATWG-0.md
category: reference
title: WHATWG - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/WHATWG
date_saved: 2026-05-05T05:48:49.174675+00:00
instance: kb-cron
parent: whatwg-glossary-mdn-20260505-0
summary:
* [Skip to main content](https://developer.mozilla.org/en-US/docs/Glossary/WHATWG#content) * [Skip to search](https://developer.mozilla.org/en-US/docs/Glossary/WHATWG#search) [ MDN ](https://developer.mozilla.org/en-US/) HTML [HTML: Markup language](https://developer.mozilla.org/en-US/docs/Web/HTML) HTML reference * [Elements](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements) * [Global attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes) * [Attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Attributes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference "See all HTML references") HTML guides * [Responsive images](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Responsive_images) * [HTML cheatsheet](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Cheatsheet) * [Date & time formats](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Date_and_time_formats) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides "See all HTML guides") Markup languages * [SVG](https://developer.mozilla.org/en-US/docs/Web/SVG) * [MathML](https://developer.mozilla.org/en-US/docs/Web/MathML) * [XML](https://developer.mozilla.org/en-US/docs/Web/XML) CSS [CSS: Styling language](https://developer.mozilla.org/en-US/docs/Web/CSS) CSS reference * [Properties](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties) * [Selectors](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors) * [At-rules](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/At-rules) * [Values](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference "See all CSS references") CSS guides * [Box model](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Box_model/Introduction) * [Animations](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Animations/Using) * [Flexbox](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Flexible_box_layout/Basic_concepts) * [Colors](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Colors/Applying_color) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides "See all CSS guides") Layout cookbook * [Column layouts](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Column_layouts) * [Centering an element](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Center_an_element) * [Card component](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Card) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook) JavaScriptJS [JavaScript: Scripting language](https://developer.mozilla.org/en-US/docs/Web/JavaScript) JS reference * [Standard built-in objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects) * [Expressions & operators](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators) * [Statements & declarations](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements) * [Functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference "See all JavaScript references") JS guides * [Control flow & error handing](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Control_flow_and_error_handling) * [Loops and iteration](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration) * [Working with objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_objects) * [Using classes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_classes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide "See all JavaScript guides") Web APIs [Web APIs: Programming interfaces](https://developer.mozilla.org/en-US/docs/Web/API) Web API reference * [File system API](https://developer.mozilla.org/en-US/docs/Web/API/File_System_API) * [Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) * [Geolocation API](https://developer.mozilla.org/en-US/docs/Web/API/Geolocation_API) * [HTML DOM API](https://developer.mozilla.org/en-US/docs/Web/API/HTML_DOM_API) * [Push API](https://developer.mozilla.org/en-US/docs/Web/API/Push_API) * [Service worker API](https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API) * [See all…](https://developer.mozilla.org/en-US/docs/Web/API


id: whatwg-glossary-mdn-20260505-1
file: data/developer.mozilla.org/en-US/docs/Glossary/WHATWG-1.md
category: reference
title: WHATWG - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/WHATWG
date_saved: 2026-05-05T05:48:49.174675+00:00
instance: kb-cron
parent: whatwg-glossary-mdn-20260505-0
summary:
## Help improve MDN [Learn how to contribute](https://developer.mozilla.org/en-US/docs/MDN/Community/Getting_started) This page was last modified on Jul 11, 2025 by [MDN contributors](https://developer.mozilla.org/en-US/docs/Glossary/WHATWG/contributors.txt). [View this page on GitHub](https://github.com/mdn/content/blob/main/files/en-us/glossary/whatwg/index.md?plain=1 "Folder: en-us/glossary/whatwg \(Opens in a new tab\)") • [Report a problem with this content](https://github.com/mdn/content/issues/new?template=page-report.yml&mdn-url=https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FWHATWG&metadata=%3C%21--+Do+not+make+changes+below+this+line+--%3E%0A%3Cdetails%3E%0A%3Csummary%3EPage+report+details%3C%2Fsummary%3E%0A%0A*+Folder%3A+%60en-us%2Fglossary%2Fwhatwg%60%0A*+MDN+URL%3A+https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FWHATWG%0A*+GitHub+URL%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fblob%2Fmain%2Ffiles%2Fen-us%2Fglossary%2Fwhatwg%2Findex.md%0A*+Last+commit%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fcommit%2F2547f622337d6cbf8c3794776b17ed377d6aad57%0A*+Document+last+modified%3A+2025-07-11T14%3A45%3A59.000Z%0A%0A%3C%2Fdetails%3E "This will take you to GitHub to file a new issue.") 1. [Glossary](https://developer.mozilla.org/en-US/docs/Glossary) 2. 1. [Abstraction](https://developer.mozilla.org/en-US/docs/Glossary/Abstraction) 2. [Accent](https://developer.mozilla.org/en-US/docs/Glossary/Accent) 3. [Accessibility](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility) 4. [Accessibility tree](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility_tree) 5. [Accessible description](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_description) 6. [Accessible name](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_name) 7. [Adobe Flash](https://developer.mozilla.org/en-US/docs/Glossary/Adobe_Flash) 8. [Advance measure](https://developer.mozilla.org/en-US/docs/Glossary/Advance_measure) 9. [Ajax](https://developer.mozilla.org/en-US/docs/Glossary/AJAX) 10. [Algorithm](https://developer.mozilla.org/en-US/docs/Glossary/Algorithm) 11. [Alignment container](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Container) 12. [Alignment subject](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Subject) 13. [Alpha (alpha channel)](https://developer.mozilla.org/en-US/docs/Glossary/Alpha) 14. [ALPN](https://developer.mozilla.org/en-US/docs/Glossary/ALPN) 15. [API](https://developer.mozilla.org/en-US/docs/Glossary/API) 16. [Apple Safari](https://developer.mozilla.org/en-US/docs/Glossary/Apple_Safari) 17. [Application context](https://developer.mozilla.org/en-US/docs/Glossary/Application_context) 18. [Argument](https://developer.mozilla.org/en-US/docs/Glossary/Argument) 19. [ARIA](https://developer.mozilla.org/en-US/docs/Glossary/ARIA) 20. [ARPA](https://developer.mozilla.org/en-US/docs/Glossary/ARPA) 21. [ARPANET](https://developer.mozilla.org/en-US/docs/Glossary/Arpanet) 22. [Array](https://developer.mozilla.org/en-US/docs/Glossary/Array) 23. [ASCII](https://developer.mozilla.org/en-US/docs/Glossary/ASCII) 24. [Aspect ratio](https://developer.mozilla.org/en-US/docs/Glossary/Aspect_ratio) 25. [Asynchronous](https://developer.mozilla.org/en-US/docs/Glossary/Asynchronous) 26. [ATAG](https://developer.mozilla.org/en-US/docs/Glossary/ATAG) 27. [Attribute](https://developer.mozilla.org/en-US/docs/Glossary/Attribute) 28. [Authentication](https://developer.mozilla.org/en-US/docs/Glossary/Authentication) 29. [Authenticator](https://developer.mozilla.org/en-US/docs/Glossary/Authenticator) 30. [Bandwidth](https://developer.mozilla.org/en-US/docs/Glossary/Bandwidth) 31. [Base64](https://developer.mozilla.org/en-US/docs/Glossary/Base64) 32. [Baseline](https://developer.mozilla.org/en-US/docs/Glossary/Baseline) 1. [Baseline (compatibility)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Compatibility) 2. [Baseline (typography)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Typography) 33. [BCP 47 language tag](https://developer.mozilla.org/en-US/docs/Glossary/BCP_47_language_tag) 34. [Beacon](https://developer.mozilla.org/en-US/docs/Glossary/Beacon) 35. [Bézier curve](https://developer.mozilla.org/en-US/docs/Glossary/Bezier_curve) 36. [bfcache](https://developer.mozilla.org/en-US/docs/Glossary/bfcache) 37. [BiDi](https://developer.mozilla.org/en-US/docs/Glossary/BiDi) 38. [BigInt](https://developer.mozilla.org/en-US/docs/Glossary/BigInt) 39. [Binding](https://developer.mozilla.org/en-US/docs/Glossary/Binding) 40. [Bitwise flags](https://developer.mozilla.org/en-US/docs/Glossary/Bitwise_flags) 41. [Blink](https://developer.mozilla.org/en-US/docs/Glossary/Blink) 42. [blink element (<blink> tag)](https://developer.mozilla.org/en-US/docs/Glossary/blink_element) 43. [Block](https://developer.mozilla.org/en-US/docs/Glossary/Block) 1. [Block (CSS)](https://developer.mozilla.org/en-US/docs/Glossary/Block/CSS) 2. [Block (scripting)](https://developer.mozilla.org/en-US/docs/Glossary/Block/Scripting) 44. [Block cipher mode of operation](https://developer.mozilla.org/en-US/docs/Glossary/Block_cipher_mode_of_operation) 45. [Block-level content](https://developer.mozilla.org/en-US/docs/Glossary/Block-level_content) 46. [Boolean](https://developer.mozilla.org/en-US/docs/Glossary/Boolean) 1. [Boolean (JavaScript)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/JavaScript) 2. [Boolean attribute (ARIA)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/ARIA) 3. [Boolean attribute (HTML)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/HTML) 47. [Bounding box](https://developer.mozilla.org/en-US/docs/Glossary/Bounding_box) 48. [Breadcrumb](https://developer.mozilla.org/en-US/docs/Glossary/Breadcrumb) 49. [Brotli


id: webassembly-glossary-mdn-20260505-0
file: data/developer.mozilla.org/en-US/docs/Glossary/WebAssembly-0.md
category: reference
title: WebAssembly - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/WebAssembly
date_saved: 2026-05-05T05:48:51.466136+00:00
instance: kb-cron
parent: webassembly-glossary-mdn-20260505-0
summary:
* [Skip to main content](https://developer.mozilla.org/en-US/docs/Glossary/WebAssembly#content) * [Skip to search](https://developer.mozilla.org/en-US/docs/Glossary/WebAssembly#search) [ MDN ](https://developer.mozilla.org/en-US/) HTML [HTML: Markup language](https://developer.mozilla.org/en-US/docs/Web/HTML) HTML reference * [Elements](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements) * [Global attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes) * [Attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Attributes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference "See all HTML references") HTML guides * [Responsive images](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Responsive_images) * [HTML cheatsheet](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Cheatsheet) * [Date & time formats](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Date_and_time_formats) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides "See all HTML guides") Markup languages * [SVG](https://developer.mozilla.org/en-US/docs/Web/SVG) * [MathML](https://developer.mozilla.org/en-US/docs/Web/MathML) * [XML](https://developer.mozilla.org/en-US/docs/Web/XML) CSS [CSS: Styling language](https://developer.mozilla.org/en-US/docs/Web/CSS) CSS reference * [Properties](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties) * [Selectors](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors) * [At-rules](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/At-rules) * [Values](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference "See all CSS references") CSS guides * [Box model](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Box_model/Introduction) * [Animations](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Animations/Using) * [Flexbox](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Flexible_box_layout/Basic_concepts) * [Colors](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Colors/Applying_color) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides "See all CSS guides") Layout cookbook * [Column layouts](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Column_layouts) * [Centering an element](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Center_an_element) * [Card component](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Card) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook) JavaScriptJS [JavaScript: Scripting language](https://developer.mozilla.org/en-US/docs/Web/JavaScript) JS reference * [Standard built-in objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects) * [Expressions & operators](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators) * [Statements & declarations](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements) * [Functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference "See all JavaScript references") JS guides * [Control flow & error handing](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Control_flow_and_error_handling) * [Loops and iteration](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration) * [Working with objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_objects) * [Using classes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_classes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide "See all JavaScript guides") Web APIs [Web APIs: Programming interfaces](https://developer.mozilla.org/en-US/docs/Web/API) Web API reference * [File system API](https://developer.mozilla.org/en-US/docs/Web/API/File_System_API) * [Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) * [Geolocation API](https://developer.mozilla.org/en-US/docs/Web/API/Geolocation_API) * [HTML DOM API](https://developer.mozilla.org/en-US/docs/Web/API/HTML_DOM_API) * [Push API](https://developer.mozilla.org/en-US/docs/Web/API/Push_API) * [Service worker API](https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API) * [See all…](https://developer.mozilla.org/en-US/docs/Web/API


id: webassembly-glossary-mdn-20260505-1
file: data/developer.mozilla.org/en-US/docs/Glossary/WebAssembly-1.md
category: reference
title: WebAssembly - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/WebAssembly
date_saved: 2026-05-05T05:48:51.466136+00:00
instance: kb-cron
parent: webassembly-glossary-mdn-20260505-0
summary:
## Help improve MDN [Learn how to contribute](https://developer.mozilla.org/en-US/docs/MDN/Community/Getting_started) This page was last modified on Jul 11, 2025 by [MDN contributors](https://developer.mozilla.org/en-US/docs/Glossary/WebAssembly/contributors.txt). [View this page on GitHub](https://github.com/mdn/content/blob/main/files/en-us/glossary/webassembly/index.md?plain=1 "Folder: en-us/glossary/webassembly \(Opens in a new tab\)") • [Report a problem with this content](https://github.com/mdn/content/issues/new?template=page-report.yml&mdn-url=https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FWebAssembly&metadata=%3C%21--+Do+not+make+changes+below+this+line+--%3E%0A%3Cdetails%3E%0A%3Csummary%3EPage+report+details%3C%2Fsummary%3E%0A%0A*+Folder%3A+%60en-us%2Fglossary%2Fwebassembly%60%0A*+MDN+URL%3A+https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FWebAssembly%0A*+GitHub+URL%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fblob%2Fmain%2Ffiles%2Fen-us%2Fglossary%2Fwebassembly%2Findex.md%0A*+Last+commit%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fcommit%2F2547f622337d6cbf8c3794776b17ed377d6aad57%0A*+Document+last+modified%3A+2025-07-11T14%3A45%3A59.000Z%0A%0A%3C%2Fdetails%3E "This will take you to GitHub to file a new issue.") 1. [Glossary](https://developer.mozilla.org/en-US/docs/Glossary) 2. 1. [Abstraction](https://developer.mozilla.org/en-US/docs/Glossary/Abstraction) 2. [Accent](https://developer.mozilla.org/en-US/docs/Glossary/Accent) 3. [Accessibility](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility) 4. [Accessibility tree](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility_tree) 5. [Accessible description](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_description) 6. [Accessible name](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_name) 7. [Adobe Flash](https://developer.mozilla.org/en-US/docs/Glossary/Adobe_Flash) 8. [Advance measure](https://developer.mozilla.org/en-US/docs/Glossary/Advance_measure) 9. [Ajax](https://developer.mozilla.org/en-US/docs/Glossary/AJAX) 10. [Algorithm](https://developer.mozilla.org/en-US/docs/Glossary/Algorithm) 11. [Alignment container](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Container) 12. [Alignment subject](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Subject) 13. [Alpha (alpha channel)](https://developer.mozilla.org/en-US/docs/Glossary/Alpha) 14. [ALPN](https://developer.mozilla.org/en-US/docs/Glossary/ALPN) 15. [API](https://developer.mozilla.org/en-US/docs/Glossary/API) 16. [Apple Safari](https://developer.mozilla.org/en-US/docs/Glossary/Apple_Safari) 17. [Application context](https://developer.mozilla.org/en-US/docs/Glossary/Application_context) 18. [Argument](https://developer.mozilla.org/en-US/docs/Glossary/Argument) 19. [ARIA](https://developer.mozilla.org/en-US/docs/Glossary/ARIA) 20. [ARPA](https://developer.mozilla.org/en-US/docs/Glossary/ARPA) 21. [ARPANET](https://developer.mozilla.org/en-US/docs/Glossary/Arpanet) 22. [Array](https://developer.mozilla.org/en-US/docs/Glossary/Array) 23. [ASCII](https://developer.mozilla.org/en-US/docs/Glossary/ASCII) 24. [Aspect ratio](https://developer.mozilla.org/en-US/docs/Glossary/Aspect_ratio) 25. [Asynchronous](https://developer.mozilla.org/en-US/docs/Glossary/Asynchronous) 26. [ATAG](https://developer.mozilla.org/en-US/docs/Glossary/ATAG) 27. [Attribute](https://developer.mozilla.org/en-US/docs/Glossary/Attribute) 28. [Authentication](https://developer.mozilla.org/en-US/docs/Glossary/Authentication) 29. [Authenticator](https://developer.mozilla.org/en-US/docs/Glossary/Authenticator) 30. [Bandwidth](https://developer.mozilla.org/en-US/docs/Glossary/Bandwidth) 31. [Base64](https://developer.mozilla.org/en-US/docs/Glossary/Base64) 32. [Baseline](https://developer.mozilla.org/en-US/docs/Glossary/Baseline) 1. [Baseline (compatibility)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Compatibility) 2. [Baseline (typography)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Typography) 33. [BCP 47 language tag](https://developer.mozilla.org/en-US/docs/Glossary/BCP_47_language_tag) 34. [Beacon](https://developer.mozilla.org/en-US/docs/Glossary/Beacon) 35. [Bézier curve](https://developer.mozilla.org/en-US/docs/Glossary/Bezier_curve) 36. [bfcache](https://developer.mozilla.org/en-US/docs/Glossary/bfcache) 37. [BiDi](https://developer.mozilla.org/en-US/docs/Glossary/BiDi) 38. [BigInt](https://developer.mozilla.org/en-US/docs/Glossary/BigInt) 39. [Binding](https://developer.mozilla.org/en-US/docs/Glossary/Binding) 40. [Bitwise flags](https://developer.mozilla.org/en-US/docs/Glossary/Bitwise_flags) 41. [Blink](https://developer.mozilla.org/en-US/docs/Glossary/Blink) 42. [blink element (<blink> tag)](https://developer.mozilla.org/en-US/docs/Glossary/blink_element) 43. [Block](https://developer.mozilla.org/en-US/docs/Glossary/Block) 1. [Block (CSS)](https://developer.mozilla.org/en-US/docs/Glossary/Block/CSS) 2. [Block (scripting)](https://developer.mozilla.org/en-US/docs/Glossary/Block/Scripting) 44. [Block cipher mode of operation](https://developer.mozilla.org/en-US/docs/Glossary/Block_cipher_mode_of_operation) 45. [Block-level content](https://developer.mozilla.org/en-US/docs/Glossary/Block-level_content) 46. [Boolean](https://developer.mozilla.org/en-US/docs/Glossary/Boolean) 1. [Boolean (JavaScript)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/JavaScript) 2. [Boolean attribute (ARIA)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/ARIA) 3. [Boolean attribute (HTML)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/HTML) 47. [Bounding box](https://developer.mozilla.org/en-US/docs/Glossary/Bounding_box) 48. [Breadcrumb](https://developer.mozilla.org/en-US/docs/Glossary/Breadcrumb) 49. [Brotli


id: webdav-glossary-mdn-20260505-0
file: data/developer.mozilla.org/en-US/docs/Glossary/WebDAV-0.md
category: reference
title: WebDAV - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/WebDAV
date_saved: 2026-05-05T05:48:54.120783+00:00
instance: kb-cron
parent: webdav-glossary-mdn-20260505-0
summary:
* [Skip to main content](https://developer.mozilla.org/en-US/docs/Glossary/WebDAV#content) * [Skip to search](https://developer.mozilla.org/en-US/docs/Glossary/WebDAV#search) [ MDN ](https://developer.mozilla.org/en-US/) HTML [HTML: Markup language](https://developer.mozilla.org/en-US/docs/Web/HTML) HTML reference * [Elements](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements) * [Global attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes) * [Attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Attributes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference "See all HTML references") HTML guides * [Responsive images](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Responsive_images) * [HTML cheatsheet](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Cheatsheet) * [Date & time formats](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Date_and_time_formats) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides "See all HTML guides") Markup languages * [SVG](https://developer.mozilla.org/en-US/docs/Web/SVG) * [MathML](https://developer.mozilla.org/en-US/docs/Web/MathML) * [XML](https://developer.mozilla.org/en-US/docs/Web/XML) CSS [CSS: Styling language](https://developer.mozilla.org/en-US/docs/Web/CSS) CSS reference * [Properties](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties) * [Selectors](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors) * [At-rules](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/At-rules) * [Values](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference "See all CSS references") CSS guides * [Box model](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Box_model/Introduction) * [Animations](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Animations/Using) * [Flexbox](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Flexible_box_layout/Basic_concepts) * [Colors](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Colors/Applying_color) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides "See all CSS guides") Layout cookbook * [Column layouts](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Column_layouts) * [Centering an element](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Center_an_element) * [Card component](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Card) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook) JavaScriptJS [JavaScript: Scripting language](https://developer.mozilla.org/en-US/docs/Web/JavaScript) JS reference * [Standard built-in objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects) * [Expressions & operators](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators) * [Statements & declarations](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements) * [Functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference "See all JavaScript references") JS guides * [Control flow & error handing](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Control_flow_and_error_handling) * [Loops and iteration](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration) * [Working with objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_objects) * [Using classes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_classes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide "See all JavaScript guides") Web APIs [Web APIs: Programming interfaces](https://developer.mozilla.org/en-US/docs/Web/API) Web API reference * [File system API](https://developer.mozilla.org/en-US/docs/Web/API/File_System_API) * [Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) * [Geolocation API](https://developer.mozilla.org/en-US/docs/Web/API/Geolocation_API) * [HTML DOM API](https://developer.mozilla.org/en-US/docs/Web/API/HTML_DOM_API) * [Push API](https://developer.mozilla.org/en-US/docs/Web/API/Push_API) * [Service worker API](https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API) * [See all…](https://developer.mozilla.org/en-US/docs/Web/API


id: webdav-glossary-mdn-20260505-1
file: data/developer.mozilla.org/en-US/docs/Glossary/WebDAV-1.md
category: reference
title: WebDAV - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/WebDAV
date_saved: 2026-05-05T05:48:54.120783+00:00
instance: kb-cron
parent: webdav-glossary-mdn-20260505-0
summary:
## Help improve MDN [Learn how to contribute](https://developer.mozilla.org/en-US/docs/MDN/Community/Getting_started) This page was last modified on Jul 11, 2025 by [MDN contributors](https://developer.mozilla.org/en-US/docs/Glossary/WebDAV/contributors.txt). [View this page on GitHub](https://github.com/mdn/content/blob/main/files/en-us/glossary/webdav/index.md?plain=1 "Folder: en-us/glossary/webdav \(Opens in a new tab\)") • [Report a problem with this content](https://github.com/mdn/content/issues/new?template=page-report.yml&mdn-url=https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FWebDAV&metadata=%3C%21--+Do+not+make+changes+below+this+line+--%3E%0A%3Cdetails%3E%0A%3Csummary%3EPage+report+details%3C%2Fsummary%3E%0A%0A*+Folder%3A+%60en-us%2Fglossary%2Fwebdav%60%0A*+MDN+URL%3A+https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FWebDAV%0A*+GitHub+URL%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fblob%2Fmain%2Ffiles%2Fen-us%2Fglossary%2Fwebdav%2Findex.md%0A*+Last+commit%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fcommit%2F2547f622337d6cbf8c3794776b17ed377d6aad57%0A*+Document+last+modified%3A+2025-07-11T14%3A45%3A59.000Z%0A%0A%3C%2Fdetails%3E "This will take you to GitHub to file a new issue.") 1. [Glossary](https://developer.mozilla.org/en-US/docs/Glossary) 2. 1. [Abstraction](https://developer.mozilla.org/en-US/docs/Glossary/Abstraction) 2. [Accent](https://developer.mozilla.org/en-US/docs/Glossary/Accent) 3. [Accessibility](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility) 4. [Accessibility tree](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility_tree) 5. [Accessible description](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_description) 6. [Accessible name](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_name) 7. [Adobe Flash](https://developer.mozilla.org/en-US/docs/Glossary/Adobe_Flash) 8. [Advance measure](https://developer.mozilla.org/en-US/docs/Glossary/Advance_measure) 9. [Ajax](https://developer.mozilla.org/en-US/docs/Glossary/AJAX) 10. [Algorithm](https://developer.mozilla.org/en-US/docs/Glossary/Algorithm) 11. [Alignment container](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Container) 12. [Alignment subject](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Subject) 13. [Alpha (alpha channel)](https://developer.mozilla.org/en-US/docs/Glossary/Alpha) 14. [ALPN](https://developer.mozilla.org/en-US/docs/Glossary/ALPN) 15. [API](https://developer.mozilla.org/en-US/docs/Glossary/API) 16. [Apple Safari](https://developer.mozilla.org/en-US/docs/Glossary/Apple_Safari) 17. [Application context](https://developer.mozilla.org/en-US/docs/Glossary/Application_context) 18. [Argument](https://developer.mozilla.org/en-US/docs/Glossary/Argument) 19. [ARIA](https://developer.mozilla.org/en-US/docs/Glossary/ARIA) 20. [ARPA](https://developer.mozilla.org/en-US/docs/Glossary/ARPA) 21. [ARPANET](https://developer.mozilla.org/en-US/docs/Glossary/Arpanet) 22. [Array](https://developer.mozilla.org/en-US/docs/Glossary/Array) 23. [ASCII](https://developer.mozilla.org/en-US/docs/Glossary/ASCII) 24. [Aspect ratio](https://developer.mozilla.org/en-US/docs/Glossary/Aspect_ratio) 25. [Asynchronous](https://developer.mozilla.org/en-US/docs/Glossary/Asynchronous) 26. [ATAG](https://developer.mozilla.org/en-US/docs/Glossary/ATAG) 27. [Attribute](https://developer.mozilla.org/en-US/docs/Glossary/Attribute) 28. [Authentication](https://developer.mozilla.org/en-US/docs/Glossary/Authentication) 29. [Authenticator](https://developer.mozilla.org/en-US/docs/Glossary/Authenticator) 30. [Bandwidth](https://developer.mozilla.org/en-US/docs/Glossary/Bandwidth) 31. [Base64](https://developer.mozilla.org/en-US/docs/Glossary/Base64) 32. [Baseline](https://developer.mozilla.org/en-US/docs/Glossary/Baseline) 1. [Baseline (compatibility)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Compatibility) 2. [Baseline (typography)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Typography) 33. [BCP 47 language tag](https://developer.mozilla.org/en-US/docs/Glossary/BCP_47_language_tag) 34. [Beacon](https://developer.mozilla.org/en-US/docs/Glossary/Beacon) 35. [Bézier curve](https://developer.mozilla.org/en-US/docs/Glossary/Bezier_curve) 36. [bfcache](https://developer.mozilla.org/en-US/docs/Glossary/bfcache) 37. [BiDi](https://developer.mozilla.org/en-US/docs/Glossary/BiDi) 38. [BigInt](https://developer.mozilla.org/en-US/docs/Glossary/BigInt) 39. [Binding](https://developer.mozilla.org/en-US/docs/Glossary/Binding) 40. [Bitwise flags](https://developer.mozilla.org/en-US/docs/Glossary/Bitwise_flags) 41. [Blink](https://developer.mozilla.org/en-US/docs/Glossary/Blink) 42. [blink element (<blink> tag)](https://developer.mozilla.org/en-US/docs/Glossary/blink_element) 43. [Block](https://developer.mozilla.org/en-US/docs/Glossary/Block) 1. [Block (CSS)](https://developer.mozilla.org/en-US/docs/Glossary/Block/CSS) 2. [Block (scripting)](https://developer.mozilla.org/en-US/docs/Glossary/Block/Scripting) 44. [Block cipher mode of operation](https://developer.mozilla.org/en-US/docs/Glossary/Block_cipher_mode_of_operation) 45. [Block-level content](https://developer.mozilla.org/en-US/docs/Glossary/Block-level_content) 46. [Boolean](https://developer.mozilla.org/en-US/docs/Glossary/Boolean) 1. [Boolean (JavaScript)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/JavaScript) 2. [Boolean attribute (ARIA)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/ARIA) 3. [Boolean attribute (HTML)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/HTML) 47. [Bounding box](https://developer.mozilla.org/en-US/docs/Glossary/Bounding_box) 48. [Breadcrumb](https://developer.mozilla.org/en-US/docs/Glossary/Breadcrumb) 49. [Brotli


id: webextensions-glossary-mdn-20260505-0
file: data/developer.mozilla.org/en-US/docs/Glossary/WebExtensions-0.md
category: reference
title: WebExtensions - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/WebExtensions
date_saved: 2026-05-05T05:48:56.573416+00:00
instance: kb-cron
parent: webextensions-glossary-mdn-20260505-0
summary:
* [Skip to main content](https://developer.mozilla.org/en-US/docs/Glossary/WebExtensions#content) * [Skip to search](https://developer.mozilla.org/en-US/docs/Glossary/WebExtensions#search) [ MDN ](https://developer.mozilla.org/en-US/) HTML [HTML: Markup language](https://developer.mozilla.org/en-US/docs/Web/HTML) HTML reference * [Elements](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements) * [Global attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes) * [Attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Attributes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference "See all HTML references") HTML guides * [Responsive images](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Responsive_images) * [HTML cheatsheet](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Cheatsheet) * [Date & time formats](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Date_and_time_formats) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides "See all HTML guides") Markup languages * [SVG](https://developer.mozilla.org/en-US/docs/Web/SVG) * [MathML](https://developer.mozilla.org/en-US/docs/Web/MathML) * [XML](https://developer.mozilla.org/en-US/docs/Web/XML) CSS [CSS: Styling language](https://developer.mozilla.org/en-US/docs/Web/CSS) CSS reference * [Properties](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties) * [Selectors](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors) * [At-rules](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/At-rules) * [Values](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference "See all CSS references") CSS guides * [Box model](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Box_model/Introduction) * [Animations](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Animations/Using) * [Flexbox](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Flexible_box_layout/Basic_concepts) * [Colors](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Colors/Applying_color) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides "See all CSS guides") Layout cookbook * [Column layouts](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Column_layouts) * [Centering an element](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Center_an_element) * [Card component](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Card) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook) JavaScriptJS [JavaScript: Scripting language](https://developer.mozilla.org/en-US/docs/Web/JavaScript) JS reference * [Standard built-in objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects) * [Expressions & operators](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators) * [Statements & declarations](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements) * [Functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference "See all JavaScript references") JS guides * [Control flow & error handing](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Control_flow_and_error_handling) * [Loops and iteration](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration) * [Working with objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_objects) * [Using classes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_classes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide "See all JavaScript guides") Web APIs [Web APIs: Programming interfaces](https://developer.mozilla.org/en-US/docs/Web/API) Web API reference * [File system API](https://developer.mozilla.org/en-US/docs/Web/API/File_System_API) * [Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) * [Geolocation API](https://developer.mozilla.org/en-US/docs/Web/API/Geolocation_API) * [HTML DOM API](https://developer.mozilla.org/en-US/docs/Web/API/HTML_DOM_API) * [Push API](https://developer.mozilla.org/en-US/docs/Web/API/Push_API) * [Service worker API](https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API) * [See all…](https://developer.mozilla.org/en-US/docs/Web/API


id: webextensions-glossary-mdn-20260505-1
file: data/developer.mozilla.org/en-US/docs/Glossary/WebExtensions-1.md
category: reference
title: WebExtensions - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/WebExtensions
date_saved: 2026-05-05T05:48:56.573416+00:00
instance: kb-cron
parent: webextensions-glossary-mdn-20260505-0
summary:
## Help improve MDN [Learn how to contribute](https://developer.mozilla.org/en-US/docs/MDN/Community/Getting_started) This page was last modified on Jul 11, 2025 by [MDN contributors](https://developer.mozilla.org/en-US/docs/Glossary/WebExtensions/contributors.txt). [View this page on GitHub](https://github.com/mdn/content/blob/main/files/en-us/glossary/webextensions/index.md?plain=1 "Folder: en-us/glossary/webextensions \(Opens in a new tab\)") • [Report a problem with this content](https://github.com/mdn/content/issues/new?template=page-report.yml&mdn-url=https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FWebExtensions&metadata=%3C%21--+Do+not+make+changes+below+this+line+--%3E%0A%3Cdetails%3E%0A%3Csummary%3EPage+report+details%3C%2Fsummary%3E%0A%0A*+Folder%3A+%60en-us%2Fglossary%2Fwebextensions%60%0A*+MDN+URL%3A+https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FWebExtensions%0A*+GitHub+URL%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fblob%2Fmain%2Ffiles%2Fen-us%2Fglossary%2Fwebextensions%2Findex.md%0A*+Last+commit%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fcommit%2F2547f622337d6cbf8c3794776b17ed377d6aad57%0A*+Document+last+modified%3A+2025-07-11T14%3A45%3A59.000Z%0A%0A%3C%2Fdetails%3E "This will take you to GitHub to file a new issue.") 1. [Glossary](https://developer.mozilla.org/en-US/docs/Glossary) 2. 1. [Abstraction](https://developer.mozilla.org/en-US/docs/Glossary/Abstraction) 2. [Accent](https://developer.mozilla.org/en-US/docs/Glossary/Accent) 3. [Accessibility](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility) 4. [Accessibility tree](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility_tree) 5. [Accessible description](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_description) 6. [Accessible name](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_name) 7. [Adobe Flash](https://developer.mozilla.org/en-US/docs/Glossary/Adobe_Flash) 8. [Advance measure](https://developer.mozilla.org/en-US/docs/Glossary/Advance_measure) 9. [Ajax](https://developer.mozilla.org/en-US/docs/Glossary/AJAX) 10. [Algorithm](https://developer.mozilla.org/en-US/docs/Glossary/Algorithm) 11. [Alignment container](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Container) 12. [Alignment subject](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Subject) 13. [Alpha (alpha channel)](https://developer.mozilla.org/en-US/docs/Glossary/Alpha) 14. [ALPN](https://developer.mozilla.org/en-US/docs/Glossary/ALPN) 15. [API](https://developer.mozilla.org/en-US/docs/Glossary/API) 16. [Apple Safari](https://developer.mozilla.org/en-US/docs/Glossary/Apple_Safari) 17. [Application context](https://developer.mozilla.org/en-US/docs/Glossary/Application_context) 18. [Argument](https://developer.mozilla.org/en-US/docs/Glossary/Argument) 19. [ARIA](https://developer.mozilla.org/en-US/docs/Glossary/ARIA) 20. [ARPA](https://developer.mozilla.org/en-US/docs/Glossary/ARPA) 21. [ARPANET](https://developer.mozilla.org/en-US/docs/Glossary/Arpanet) 22. [Array](https://developer.mozilla.org/en-US/docs/Glossary/Array) 23. [ASCII](https://developer.mozilla.org/en-US/docs/Glossary/ASCII) 24. [Aspect ratio](https://developer.mozilla.org/en-US/docs/Glossary/Aspect_ratio) 25. [Asynchronous](https://developer.mozilla.org/en-US/docs/Glossary/Asynchronous) 26. [ATAG](https://developer.mozilla.org/en-US/docs/Glossary/ATAG) 27. [Attribute](https://developer.mozilla.org/en-US/docs/Glossary/Attribute) 28. [Authentication](https://developer.mozilla.org/en-US/docs/Glossary/Authentication) 29. [Authenticator](https://developer.mozilla.org/en-US/docs/Glossary/Authenticator) 30. [Bandwidth](https://developer.mozilla.org/en-US/docs/Glossary/Bandwidth) 31. [Base64](https://developer.mozilla.org/en-US/docs/Glossary/Base64) 32. [Baseline](https://developer.mozilla.org/en-US/docs/Glossary/Baseline) 1. [Baseline (compatibility)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Compatibility) 2. [Baseline (typography)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Typography) 33. [BCP 47 language tag](https://developer.mozilla.org/en-US/docs/Glossary/BCP_47_language_tag) 34. [Beacon](https://developer.mozilla.org/en-US/docs/Glossary/Beacon) 35. [Bézier curve](https://developer.mozilla.org/en-US/docs/Glossary/Bezier_curve) 36. [bfcache](https://developer.mozilla.org/en-US/docs/Glossary/bfcache) 37. [BiDi](https://developer.mozilla.org/en-US/docs/Glossary/BiDi) 38. [BigInt](https://developer.mozilla.org/en-US/docs/Glossary/BigInt) 39. [Binding](https://developer.mozilla.org/en-US/docs/Glossary/Binding) 40. [Bitwise flags](https://developer.mozilla.org/en-US/docs/Glossary/Bitwise_flags) 41. [Blink](https://developer.mozilla.org/en-US/docs/Glossary/Blink) 42. [blink element (<blink> tag)](https://developer.mozilla.org/en-US/docs/Glossary/blink_element) 43. [Block](https://developer.mozilla.org/en-US/docs/Glossary/Block) 1. [Block (CSS)](https://developer.mozilla.org/en-US/docs/Glossary/Block/CSS) 2. [Block (scripting)](https://developer.mozilla.org/en-US/docs/Glossary/Block/Scripting) 44. [Block cipher mode of operation](https://developer.mozilla.org/en-US/docs/Glossary/Block_cipher_mode_of_operation) 45. [Block-level content](https://developer.mozilla.org/en-US/docs/Glossary/Block-level_content) 46. [Boolean](https://developer.mozilla.org/en-US/docs/Glossary/Boolean) 1. [Boolean (JavaScript)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/JavaScript) 2. [Boolean attribute (ARIA)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/ARIA) 3. [Boolean attribute (HTML)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/HTML) 47. [Bounding box](https://developer.mozilla.org/en-US/docs/Glossary/Bounding_box) 48. [Breadcrumb](https://developer.mozilla.org/en-US/docs/Glossary/Breadcrumb) 49. [Brotli


id: webgl-glossary-mdn-20260505-0
file: data/developer.mozilla.org/en-US/docs/Glossary/WebGL-0.md
category: reference
title: WebGL - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/WebGL
date_saved: 2026-05-05T05:48:59.260653+00:00
instance: kb-cron
parent: webgl-glossary-mdn-20260505-0
summary:
* [Skip to main content](https://developer.mozilla.org/en-US/docs/Glossary/WebGL#content) * [Skip to search](https://developer.mozilla.org/en-US/docs/Glossary/WebGL#search) [ MDN ](https://developer.mozilla.org/en-US/) HTML [HTML: Markup language](https://developer.mozilla.org/en-US/docs/Web/HTML) HTML reference * [Elements](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements) * [Global attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes) * [Attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Attributes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference "See all HTML references") HTML guides * [Responsive images](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Responsive_images) * [HTML cheatsheet](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Cheatsheet) * [Date & time formats](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Date_and_time_formats) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides "See all HTML guides") Markup languages * [SVG](https://developer.mozilla.org/en-US/docs/Web/SVG) * [MathML](https://developer.mozilla.org/en-US/docs/Web/MathML) * [XML](https://developer.mozilla.org/en-US/docs/Web/XML) CSS [CSS: Styling language](https://developer.mozilla.org/en-US/docs/Web/CSS) CSS reference * [Properties](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties) * [Selectors](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors) * [At-rules](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/At-rules) * [Values](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference "See all CSS references") CSS guides * [Box model](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Box_model/Introduction) * [Animations](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Animations/Using) * [Flexbox](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Flexible_box_layout/Basic_concepts) * [Colors](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Colors/Applying_color) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides "See all CSS guides") Layout cookbook * [Column layouts](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Column_layouts) * [Centering an element](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Center_an_element) * [Card component](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Card) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook) JavaScriptJS [JavaScript: Scripting language](https://developer.mozilla.org/en-US/docs/Web/JavaScript) JS reference * [Standard built-in objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects) * [Expressions & operators](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators) * [Statements & declarations](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements) * [Functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference "See all JavaScript references") JS guides * [Control flow & error handing](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Control_flow_and_error_handling) * [Loops and iteration](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration) * [Working with objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_objects) * [Using classes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_classes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide "See all JavaScript guides") Web APIs [Web APIs: Programming interfaces](https://developer.mozilla.org/en-US/docs/Web/API) Web API reference * [File system API](https://developer.mozilla.org/en-US/docs/Web/API/File_System_API) * [Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) * [Geolocation API](https://developer.mozilla.org/en-US/docs/Web/API/Geolocation_API) * [HTML DOM API](https://developer.mozilla.org/en-US/docs/Web/API/HTML_DOM_API) * [Push API](https://developer.mozilla.org/en-US/docs/Web/API/Push_API) * [Service worker API](https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API) * [See all…](https://developer.mozilla.org/en-US/docs/Web/API


id: webgl-glossary-mdn-20260505-1
file: data/developer.mozilla.org/en-US/docs/Glossary/WebGL-1.md
category: reference
title: WebGL - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/WebGL
date_saved: 2026-05-05T05:48:59.260653+00:00
instance: kb-cron
parent: webgl-glossary-mdn-20260505-0
summary:
## Help improve MDN [Learn how to contribute](https://developer.mozilla.org/en-US/docs/MDN/Community/Getting_started) This page was last modified on Jul 11, 2025 by [MDN contributors](https://developer.mozilla.org/en-US/docs/Glossary/WebGL/contributors.txt). [View this page on GitHub](https://github.com/mdn/content/blob/main/files/en-us/glossary/webgl/index.md?plain=1 "Folder: en-us/glossary/webgl \(Opens in a new tab\)") • [Report a problem with this content](https://github.com/mdn/content/issues/new?template=page-report.yml&mdn-url=https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FWebGL&metadata=%3C%21--+Do+not+make+changes+below+this+line+--%3E%0A%3Cdetails%3E%0A%3Csummary%3EPage+report+details%3C%2Fsummary%3E%0A%0A*+Folder%3A+%60en-us%2Fglossary%2Fwebgl%60%0A*+MDN+URL%3A+https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FWebGL%0A*+GitHub+URL%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fblob%2Fmain%2Ffiles%2Fen-us%2Fglossary%2Fwebgl%2Findex.md%0A*+Last+commit%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fcommit%2F2547f622337d6cbf8c3794776b17ed377d6aad57%0A*+Document+last+modified%3A+2025-07-11T14%3A45%3A59.000Z%0A%0A%3C%2Fdetails%3E "This will take you to GitHub to file a new issue.") 1. [Glossary](https://developer.mozilla.org/en-US/docs/Glossary) 2. 1. [Abstraction](https://developer.mozilla.org/en-US/docs/Glossary/Abstraction) 2. [Accent](https://developer.mozilla.org/en-US/docs/Glossary/Accent) 3. [Accessibility](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility) 4. [Accessibility tree](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility_tree) 5. [Accessible description](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_description) 6. [Accessible name](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_name) 7. [Adobe Flash](https://developer.mozilla.org/en-US/docs/Glossary/Adobe_Flash) 8. [Advance measure](https://developer.mozilla.org/en-US/docs/Glossary/Advance_measure) 9. [Ajax](https://developer.mozilla.org/en-US/docs/Glossary/AJAX) 10. [Algorithm](https://developer.mozilla.org/en-US/docs/Glossary/Algorithm) 11. [Alignment container](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Container) 12. [Alignment subject](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Subject) 13. [Alpha (alpha channel)](https://developer.mozilla.org/en-US/docs/Glossary/Alpha) 14. [ALPN](https://developer.mozilla.org/en-US/docs/Glossary/ALPN) 15. [API](https://developer.mozilla.org/en-US/docs/Glossary/API) 16. [Apple Safari](https://developer.mozilla.org/en-US/docs/Glossary/Apple_Safari) 17. [Application context](https://developer.mozilla.org/en-US/docs/Glossary/Application_context) 18. [Argument](https://developer.mozilla.org/en-US/docs/Glossary/Argument) 19. [ARIA](https://developer.mozilla.org/en-US/docs/Glossary/ARIA) 20. [ARPA](https://developer.mozilla.org/en-US/docs/Glossary/ARPA) 21. [ARPANET](https://developer.mozilla.org/en-US/docs/Glossary/Arpanet) 22. [Array](https://developer.mozilla.org/en-US/docs/Glossary/Array) 23. [ASCII](https://developer.mozilla.org/en-US/docs/Glossary/ASCII) 24. [Aspect ratio](https://developer.mozilla.org/en-US/docs/Glossary/Aspect_ratio) 25. [Asynchronous](https://developer.mozilla.org/en-US/docs/Glossary/Asynchronous) 26. [ATAG](https://developer.mozilla.org/en-US/docs/Glossary/ATAG) 27. [Attribute](https://developer.mozilla.org/en-US/docs/Glossary/Attribute) 28. [Authentication](https://developer.mozilla.org/en-US/docs/Glossary/Authentication) 29. [Authenticator](https://developer.mozilla.org/en-US/docs/Glossary/Authenticator) 30. [Bandwidth](https://developer.mozilla.org/en-US/docs/Glossary/Bandwidth) 31. [Base64](https://developer.mozilla.org/en-US/docs/Glossary/Base64) 32. [Baseline](https://developer.mozilla.org/en-US/docs/Glossary/Baseline) 1. [Baseline (compatibility)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Compatibility) 2. [Baseline (typography)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Typography) 33. [BCP 47 language tag](https://developer.mozilla.org/en-US/docs/Glossary/BCP_47_language_tag) 34. [Beacon](https://developer.mozilla.org/en-US/docs/Glossary/Beacon) 35. [Bézier curve](https://developer.mozilla.org/en-US/docs/Glossary/Bezier_curve) 36. [bfcache](https://developer.mozilla.org/en-US/docs/Glossary/bfcache) 37. [BiDi](https://developer.mozilla.org/en-US/docs/Glossary/BiDi) 38. [BigInt](https://developer.mozilla.org/en-US/docs/Glossary/BigInt) 39. [Binding](https://developer.mozilla.org/en-US/docs/Glossary/Binding) 40. [Bitwise flags](https://developer.mozilla.org/en-US/docs/Glossary/Bitwise_flags) 41. [Blink](https://developer.mozilla.org/en-US/docs/Glossary/Blink) 42. [blink element (<blink> tag)](https://developer.mozilla.org/en-US/docs/Glossary/blink_element) 43. [Block](https://developer.mozilla.org/en-US/docs/Glossary/Block) 1. [Block (CSS)](https://developer.mozilla.org/en-US/docs/Glossary/Block/CSS) 2. [Block (scripting)](https://developer.mozilla.org/en-US/docs/Glossary/Block/Scripting) 44. [Block cipher mode of operation](https://developer.mozilla.org/en-US/docs/Glossary/Block_cipher_mode_of_operation) 45. [Block-level content](https://developer.mozilla.org/en-US/docs/Glossary/Block-level_content) 46. [Boolean](https://developer.mozilla.org/en-US/docs/Glossary/Boolean) 1. [Boolean (JavaScript)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/JavaScript) 2. [Boolean attribute (ARIA)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/ARIA) 3. [Boolean attribute (HTML)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/HTML) 47. [Bounding box](https://developer.mozilla.org/en-US/docs/Glossary/Bounding_box) 48. [Breadcrumb](https://developer.mozilla.org/en-US/docs/Glossary/Breadcrumb) 49. [Brotli


id: webidl-glossary-mdn-20260505-0
file: data/developer.mozilla.org/en-US/docs/Glossary/WebIDL-0.md
category: reference
title: WebIDL - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/WebIDL
date_saved: 2026-05-05T05:49:01.796307+00:00
instance: kb-cron
parent: webidl-glossary-mdn-20260505-0
summary:
* [Skip to main content](https://developer.mozilla.org/en-US/docs/Glossary/WebIDL#content) * [Skip to search](https://developer.mozilla.org/en-US/docs/Glossary/WebIDL#search) [ MDN ](https://developer.mozilla.org/en-US/) HTML [HTML: Markup language](https://developer.mozilla.org/en-US/docs/Web/HTML) HTML reference * [Elements](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements) * [Global attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes) * [Attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Attributes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference "See all HTML references") HTML guides * [Responsive images](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Responsive_images) * [HTML cheatsheet](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Cheatsheet) * [Date & time formats](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Date_and_time_formats) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides "See all HTML guides") Markup languages * [SVG](https://developer.mozilla.org/en-US/docs/Web/SVG) * [MathML](https://developer.mozilla.org/en-US/docs/Web/MathML) * [XML](https://developer.mozilla.org/en-US/docs/Web/XML) CSS [CSS: Styling language](https://developer.mozilla.org/en-US/docs/Web/CSS) CSS reference * [Properties](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties) * [Selectors](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors) * [At-rules](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/At-rules) * [Values](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference "See all CSS references") CSS guides * [Box model](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Box_model/Introduction) * [Animations](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Animations/Using) * [Flexbox](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Flexible_box_layout/Basic_concepts) * [Colors](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Colors/Applying_color) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides "See all CSS guides") Layout cookbook * [Column layouts](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Column_layouts) * [Centering an element](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Center_an_element) * [Card component](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Card) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook) JavaScriptJS [JavaScript: Scripting language](https://developer.mozilla.org/en-US/docs/Web/JavaScript) JS reference * [Standard built-in objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects) * [Expressions & operators](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators) * [Statements & declarations](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements) * [Functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference "See all JavaScript references") JS guides * [Control flow & error handing](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Control_flow_and_error_handling) * [Loops and iteration](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration) * [Working with objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_objects) * [Using classes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_classes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide "See all JavaScript guides") Web APIs [Web APIs: Programming interfaces](https://developer.mozilla.org/en-US/docs/Web/API) Web API reference * [File system API](https://developer.mozilla.org/en-US/docs/Web/API/File_System_API) * [Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) * [Geolocation API](https://developer.mozilla.org/en-US/docs/Web/API/Geolocation_API) * [HTML DOM API](https://developer.mozilla.org/en-US/docs/Web/API/HTML_DOM_API) * [Push API](https://developer.mozilla.org/en-US/docs/Web/API/Push_API) * [Service worker API](https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API) * [See all…](https://developer.mozilla.org/en-US/docs/Web/API


id: webidl-glossary-mdn-20260505-1
file: data/developer.mozilla.org/en-US/docs/Glossary/WebIDL-1.md
category: reference
title: WebIDL - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/WebIDL
date_saved: 2026-05-05T05:49:01.796307+00:00
instance: kb-cron
parent: webidl-glossary-mdn-20260505-0
summary:
## Help improve MDN [Learn how to contribute](https://developer.mozilla.org/en-US/docs/MDN/Community/Getting_started) This page was last modified on Jul 11, 2025 by [MDN contributors](https://developer.mozilla.org/en-US/docs/Glossary/WebIDL/contributors.txt). [View this page on GitHub](https://github.com/mdn/content/blob/main/files/en-us/glossary/webidl/index.md?plain=1 "Folder: en-us/glossary/webidl \(Opens in a new tab\)") • [Report a problem with this content](https://github.com/mdn/content/issues/new?template=page-report.yml&mdn-url=https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FWebIDL&metadata=%3C%21--+Do+not+make+changes+below+this+line+--%3E%0A%3Cdetails%3E%0A%3Csummary%3EPage+report+details%3C%2Fsummary%3E%0A%0A*+Folder%3A+%60en-us%2Fglossary%2Fwebidl%60%0A*+MDN+URL%3A+https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FWebIDL%0A*+GitHub+URL%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fblob%2Fmain%2Ffiles%2Fen-us%2Fglossary%2Fwebidl%2Findex.md%0A*+Last+commit%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fcommit%2F2547f622337d6cbf8c3794776b17ed377d6aad57%0A*+Document+last+modified%3A+2025-07-11T14%3A45%3A59.000Z%0A%0A%3C%2Fdetails%3E "This will take you to GitHub to file a new issue.") 1. [Glossary](https://developer.mozilla.org/en-US/docs/Glossary) 2. 1. [Abstraction](https://developer.mozilla.org/en-US/docs/Glossary/Abstraction) 2. [Accent](https://developer.mozilla.org/en-US/docs/Glossary/Accent) 3. [Accessibility](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility) 4. [Accessibility tree](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility_tree) 5. [Accessible description](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_description) 6. [Accessible name](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_name) 7. [Adobe Flash](https://developer.mozilla.org/en-US/docs/Glossary/Adobe_Flash) 8. [Advance measure](https://developer.mozilla.org/en-US/docs/Glossary/Advance_measure) 9. [Ajax](https://developer.mozilla.org/en-US/docs/Glossary/AJAX) 10. [Algorithm](https://developer.mozilla.org/en-US/docs/Glossary/Algorithm) 11. [Alignment container](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Container) 12. [Alignment subject](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Subject) 13. [Alpha (alpha channel)](https://developer.mozilla.org/en-US/docs/Glossary/Alpha) 14. [ALPN](https://developer.mozilla.org/en-US/docs/Glossary/ALPN) 15. [API](https://developer.mozilla.org/en-US/docs/Glossary/API) 16. [Apple Safari](https://developer.mozilla.org/en-US/docs/Glossary/Apple_Safari) 17. [Application context](https://developer.mozilla.org/en-US/docs/Glossary/Application_context) 18. [Argument](https://developer.mozilla.org/en-US/docs/Glossary/Argument) 19. [ARIA](https://developer.mozilla.org/en-US/docs/Glossary/ARIA) 20. [ARPA](https://developer.mozilla.org/en-US/docs/Glossary/ARPA) 21. [ARPANET](https://developer.mozilla.org/en-US/docs/Glossary/Arpanet) 22. [Array](https://developer.mozilla.org/en-US/docs/Glossary/Array) 23. [ASCII](https://developer.mozilla.org/en-US/docs/Glossary/ASCII) 24. [Aspect ratio](https://developer.mozilla.org/en-US/docs/Glossary/Aspect_ratio) 25. [Asynchronous](https://developer.mozilla.org/en-US/docs/Glossary/Asynchronous) 26. [ATAG](https://developer.mozilla.org/en-US/docs/Glossary/ATAG) 27. [Attribute](https://developer.mozilla.org/en-US/docs/Glossary/Attribute) 28. [Authentication](https://developer.mozilla.org/en-US/docs/Glossary/Authentication) 29. [Authenticator](https://developer.mozilla.org/en-US/docs/Glossary/Authenticator) 30. [Bandwidth](https://developer.mozilla.org/en-US/docs/Glossary/Bandwidth) 31. [Base64](https://developer.mozilla.org/en-US/docs/Glossary/Base64) 32. [Baseline](https://developer.mozilla.org/en-US/docs/Glossary/Baseline) 1. [Baseline (compatibility)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Compatibility) 2. [Baseline (typography)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Typography) 33. [BCP 47 language tag](https://developer.mozilla.org/en-US/docs/Glossary/BCP_47_language_tag) 34. [Beacon](https://developer.mozilla.org/en-US/docs/Glossary/Beacon) 35. [Bézier curve](https://developer.mozilla.org/en-US/docs/Glossary/Bezier_curve) 36. [bfcache](https://developer.mozilla.org/en-US/docs/Glossary/bfcache) 37. [BiDi](https://developer.mozilla.org/en-US/docs/Glossary/BiDi) 38. [BigInt](https://developer.mozilla.org/en-US/docs/Glossary/BigInt) 39. [Binding](https://developer.mozilla.org/en-US/docs/Glossary/Binding) 40. [Bitwise flags](https://developer.mozilla.org/en-US/docs/Glossary/Bitwise_flags) 41. [Blink](https://developer.mozilla.org/en-US/docs/Glossary/Blink) 42. [blink element (<blink> tag)](https://developer.mozilla.org/en-US/docs/Glossary/blink_element) 43. [Block](https://developer.mozilla.org/en-US/docs/Glossary/Block) 1. [Block (CSS)](https://developer.mozilla.org/en-US/docs/Glossary/Block/CSS) 2. [Block (scripting)](https://developer.mozilla.org/en-US/docs/Glossary/Block/Scripting) 44. [Block cipher mode of operation](https://developer.mozilla.org/en-US/docs/Glossary/Block_cipher_mode_of_operation) 45. [Block-level content](https://developer.mozilla.org/en-US/docs/Glossary/Block-level_content) 46. [Boolean](https://developer.mozilla.org/en-US/docs/Glossary/Boolean) 1. [Boolean (JavaScript)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/JavaScript) 2. [Boolean attribute (ARIA)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/ARIA) 3. [Boolean attribute (HTML)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/HTML) 47. [Bounding box](https://developer.mozilla.org/en-US/docs/Glossary/Bounding_box) 48. [Breadcrumb](https://developer.mozilla.org/en-US/docs/Glossary/Breadcrumb) 49. [Brotli


id: webkit-glossary-mdn-20260505-0
file: data/developer.mozilla.org/en-US/docs/Glossary/WebKit-0.md
category: reference
title: WebKit - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/WebKit
date_saved: 2026-05-05T05:49:04.170954+00:00
instance: kb-cron
parent: webkit-glossary-mdn-20260505-0
summary:
* [Skip to main content](https://developer.mozilla.org/en-US/docs/Glossary/WebKit#content) * [Skip to search](https://developer.mozilla.org/en-US/docs/Glossary/WebKit#search) [ MDN ](https://developer.mozilla.org/en-US/) HTML [HTML: Markup language](https://developer.mozilla.org/en-US/docs/Web/HTML) HTML reference * [Elements](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements) * [Global attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes) * [Attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Attributes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference "See all HTML references") HTML guides * [Responsive images](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Responsive_images) * [HTML cheatsheet](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Cheatsheet) * [Date & time formats](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Date_and_time_formats) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides "See all HTML guides") Markup languages * [SVG](https://developer.mozilla.org/en-US/docs/Web/SVG) * [MathML](https://developer.mozilla.org/en-US/docs/Web/MathML) * [XML](https://developer.mozilla.org/en-US/docs/Web/XML) CSS [CSS: Styling language](https://developer.mozilla.org/en-US/docs/Web/CSS) CSS reference * [Properties](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties) * [Selectors](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors) * [At-rules](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/At-rules) * [Values](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference "See all CSS references") CSS guides * [Box model](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Box_model/Introduction) * [Animations](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Animations/Using) * [Flexbox](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Flexible_box_layout/Basic_concepts) * [Colors](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Colors/Applying_color) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides "See all CSS guides") Layout cookbook * [Column layouts](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Column_layouts) * [Centering an element](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Center_an_element) * [Card component](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Card) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook) JavaScriptJS [JavaScript: Scripting language](https://developer.mozilla.org/en-US/docs/Web/JavaScript) JS reference * [Standard built-in objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects) * [Expressions & operators](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators) * [Statements & declarations](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements) * [Functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference "See all JavaScript references") JS guides * [Control flow & error handing](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Control_flow_and_error_handling) * [Loops and iteration](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration) * [Working with objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_objects) * [Using classes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_classes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide "See all JavaScript guides") Web APIs [Web APIs: Programming interfaces](https://developer.mozilla.org/en-US/docs/Web/API) Web API reference * [File system API](https://developer.mozilla.org/en-US/docs/Web/API/File_System_API) * [Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) * [Geolocation API](https://developer.mozilla.org/en-US/docs/Web/API/Geolocation_API) * [HTML DOM API](https://developer.mozilla.org/en-US/docs/Web/API/HTML_DOM_API) * [Push API](https://developer.mozilla.org/en-US/docs/Web/API/Push_API) * [Service worker API](https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API) * [See all…](https://developer.mozilla.org/en-US/docs/Web/API


id: webkit-glossary-mdn-20260505-1
file: data/developer.mozilla.org/en-US/docs/Glossary/WebKit-1.md
category: reference
title: WebKit - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/WebKit
date_saved: 2026-05-05T05:49:04.170954+00:00
instance: kb-cron
parent: webkit-glossary-mdn-20260505-0
summary:
## Help improve MDN [Learn how to contribute](https://developer.mozilla.org/en-US/docs/MDN/Community/Getting_started) This page was last modified on Oct 28, 2025 by [MDN contributors](https://developer.mozilla.org/en-US/docs/Glossary/WebKit/contributors.txt). [View this page on GitHub](https://github.com/mdn/content/blob/main/files/en-us/glossary/webkit/index.md?plain=1 "Folder: en-us/glossary/webkit \(Opens in a new tab\)") • [Report a problem with this content](https://github.com/mdn/content/issues/new?template=page-report.yml&mdn-url=https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FWebKit&metadata=%3C%21--+Do+not+make+changes+below+this+line+--%3E%0A%3Cdetails%3E%0A%3Csummary%3EPage+report+details%3C%2Fsummary%3E%0A%0A*+Folder%3A+%60en-us%2Fglossary%2Fwebkit%60%0A*+MDN+URL%3A+https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FWebKit%0A*+GitHub+URL%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fblob%2Fmain%2Ffiles%2Fen-us%2Fglossary%2Fwebkit%2Findex.md%0A*+Last+commit%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fcommit%2F1f6d5b39a5883789ece6b570227648113c7021a1%0A*+Document+last+modified%3A+2025-10-28T16%3A22%3A04.000Z%0A%0A%3C%2Fdetails%3E "This will take you to GitHub to file a new issue.") 1. [Glossary](https://developer.mozilla.org/en-US/docs/Glossary) 2. 1. [Abstraction](https://developer.mozilla.org/en-US/docs/Glossary/Abstraction) 2. [Accent](https://developer.mozilla.org/en-US/docs/Glossary/Accent) 3. [Accessibility](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility) 4. [Accessibility tree](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility_tree) 5. [Accessible description](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_description) 6. [Accessible name](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_name) 7. [Adobe Flash](https://developer.mozilla.org/en-US/docs/Glossary/Adobe_Flash) 8. [Advance measure](https://developer.mozilla.org/en-US/docs/Glossary/Advance_measure) 9. [Ajax](https://developer.mozilla.org/en-US/docs/Glossary/AJAX) 10. [Algorithm](https://developer.mozilla.org/en-US/docs/Glossary/Algorithm) 11. [Alignment container](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Container) 12. [Alignment subject](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Subject) 13. [Alpha (alpha channel)](https://developer.mozilla.org/en-US/docs/Glossary/Alpha) 14. [ALPN](https://developer.mozilla.org/en-US/docs/Glossary/ALPN) 15. [API](https://developer.mozilla.org/en-US/docs/Glossary/API) 16. [Apple Safari](https://developer.mozilla.org/en-US/docs/Glossary/Apple_Safari) 17. [Application context](https://developer.mozilla.org/en-US/docs/Glossary/Application_context) 18. [Argument](https://developer.mozilla.org/en-US/docs/Glossary/Argument) 19. [ARIA](https://developer.mozilla.org/en-US/docs/Glossary/ARIA) 20. [ARPA](https://developer.mozilla.org/en-US/docs/Glossary/ARPA) 21. [ARPANET](https://developer.mozilla.org/en-US/docs/Glossary/Arpanet) 22. [Array](https://developer.mozilla.org/en-US/docs/Glossary/Array) 23. [ASCII](https://developer.mozilla.org/en-US/docs/Glossary/ASCII) 24. [Aspect ratio](https://developer.mozilla.org/en-US/docs/Glossary/Aspect_ratio) 25. [Asynchronous](https://developer.mozilla.org/en-US/docs/Glossary/Asynchronous) 26. [ATAG](https://developer.mozilla.org/en-US/docs/Glossary/ATAG) 27. [Attribute](https://developer.mozilla.org/en-US/docs/Glossary/Attribute) 28. [Authentication](https://developer.mozilla.org/en-US/docs/Glossary/Authentication) 29. [Authenticator](https://developer.mozilla.org/en-US/docs/Glossary/Authenticator) 30. [Bandwidth](https://developer.mozilla.org/en-US/docs/Glossary/Bandwidth) 31. [Base64](https://developer.mozilla.org/en-US/docs/Glossary/Base64) 32. [Baseline](https://developer.mozilla.org/en-US/docs/Glossary/Baseline) 1. [Baseline (compatibility)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Compatibility) 2. [Baseline (typography)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Typography) 33. [BCP 47 language tag](https://developer.mozilla.org/en-US/docs/Glossary/BCP_47_language_tag) 34. [Beacon](https://developer.mozilla.org/en-US/docs/Glossary/Beacon) 35. [Bézier curve](https://developer.mozilla.org/en-US/docs/Glossary/Bezier_curve) 36. [bfcache](https://developer.mozilla.org/en-US/docs/Glossary/bfcache) 37. [BiDi](https://developer.mozilla.org/en-US/docs/Glossary/BiDi) 38. [BigInt](https://developer.mozilla.org/en-US/docs/Glossary/BigInt) 39. [Binding](https://developer.mozilla.org/en-US/docs/Glossary/Binding) 40. [Bitwise flags](https://developer.mozilla.org/en-US/docs/Glossary/Bitwise_flags) 41. [Blink](https://developer.mozilla.org/en-US/docs/Glossary/Blink) 42. [blink element (<blink> tag)](https://developer.mozilla.org/en-US/docs/Glossary/blink_element) 43. [Block](https://developer.mozilla.org/en-US/docs/Glossary/Block) 1. [Block (CSS)](https://developer.mozilla.org/en-US/docs/Glossary/Block/CSS) 2. [Block (scripting)](https://developer.mozilla.org/en-US/docs/Glossary/Block/Scripting) 44. [Block cipher mode of operation](https://developer.mozilla.org/en-US/docs/Glossary/Block_cipher_mode_of_operation) 45. [Block-level content](https://developer.mozilla.org/en-US/docs/Glossary/Block-level_content) 46. [Boolean](https://developer.mozilla.org/en-US/docs/Glossary/Boolean) 1. [Boolean (JavaScript)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/JavaScript) 2. [Boolean attribute (ARIA)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/ARIA) 3. [Boolean attribute (HTML)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/HTML) 47. [Bounding box](https://developer.mozilla.org/en-US/docs/Glossary/Bounding_box) 48. [Breadcrumb](https://developer.mozilla.org/en-US/docs/Glossary/Breadcrumb) 49. [Brotli


id: webm-glossary-mdn-20260505-0
file: data/developer.mozilla.org/en-US/docs/Glossary/WebM-0.md
category: reference
title: WebM - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/WebM
date_saved: 2026-05-05T05:49:06.533492+00:00
instance: kb-cron
parent: webm-glossary-mdn-20260505-0
summary:
* [Skip to main content](https://developer.mozilla.org/en-US/docs/Glossary/WebM#content) * [Skip to search](https://developer.mozilla.org/en-US/docs/Glossary/WebM#search) [ MDN ](https://developer.mozilla.org/en-US/) HTML [HTML: Markup language](https://developer.mozilla.org/en-US/docs/Web/HTML) HTML reference * [Elements](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements) * [Global attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes) * [Attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Attributes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference "See all HTML references") HTML guides * [Responsive images](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Responsive_images) * [HTML cheatsheet](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Cheatsheet) * [Date & time formats](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Date_and_time_formats) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides "See all HTML guides") Markup languages * [SVG](https://developer.mozilla.org/en-US/docs/Web/SVG) * [MathML](https://developer.mozilla.org/en-US/docs/Web/MathML) * [XML](https://developer.mozilla.org/en-US/docs/Web/XML) CSS [CSS: Styling language](https://developer.mozilla.org/en-US/docs/Web/CSS) CSS reference * [Properties](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties) * [Selectors](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors) * [At-rules](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/At-rules) * [Values](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference "See all CSS references") CSS guides * [Box model](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Box_model/Introduction) * [Animations](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Animations/Using) * [Flexbox](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Flexible_box_layout/Basic_concepts) * [Colors](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Colors/Applying_color) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides "See all CSS guides") Layout cookbook * [Column layouts](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Column_layouts) * [Centering an element](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Center_an_element) * [Card component](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Card) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook) JavaScriptJS [JavaScript: Scripting language](https://developer.mozilla.org/en-US/docs/Web/JavaScript) JS reference * [Standard built-in objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects) * [Expressions & operators](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators) * [Statements & declarations](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements) * [Functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference "See all JavaScript references") JS guides * [Control flow & error handing](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Control_flow_and_error_handling) * [Loops and iteration](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration) * [Working with objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_objects) * [Using classes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_classes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide "See all JavaScript guides") Web APIs [Web APIs: Programming interfaces](https://developer.mozilla.org/en-US/docs/Web/API) Web API reference * [File system API](https://developer.mozilla.org/en-US/docs/Web/API/File_System_API) * [Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) * [Geolocation API](https://developer.mozilla.org/en-US/docs/Web/API/Geolocation_API) * [HTML DOM API](https://developer.mozilla.org/en-US/docs/Web/API/HTML_DOM_API) * [Push API](https://developer.mozilla.org/en-US/docs/Web/API/Push_API) * [Service worker API](https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API) * [See all…](https://developer.mozilla.org/en-US/docs/Web/API


id: webm-glossary-mdn-20260505-1
file: data/developer.mozilla.org/en-US/docs/Glossary/WebM-1.md
category: reference
title: WebM - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/WebM
date_saved: 2026-05-05T05:49:06.533492+00:00
instance: kb-cron
parent: webm-glossary-mdn-20260505-0
summary:
## Help improve MDN [Learn how to contribute](https://developer.mozilla.org/en-US/docs/MDN/Community/Getting_started) This page was last modified on Jul 11, 2025 by [MDN contributors](https://developer.mozilla.org/en-US/docs/Glossary/WebM/contributors.txt). [View this page on GitHub](https://github.com/mdn/content/blob/main/files/en-us/glossary/webm/index.md?plain=1 "Folder: en-us/glossary/webm \(Opens in a new tab\)") • [Report a problem with this content](https://github.com/mdn/content/issues/new?template=page-report.yml&mdn-url=https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FWebM&metadata=%3C%21--+Do+not+make+changes+below+this+line+--%3E%0A%3Cdetails%3E%0A%3Csummary%3EPage+report+details%3C%2Fsummary%3E%0A%0A*+Folder%3A+%60en-us%2Fglossary%2Fwebm%60%0A*+MDN+URL%3A+https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FWebM%0A*+GitHub+URL%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fblob%2Fmain%2Ffiles%2Fen-us%2Fglossary%2Fwebm%2Findex.md%0A*+Last+commit%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fcommit%2F2547f622337d6cbf8c3794776b17ed377d6aad57%0A*+Document+last+modified%3A+2025-07-11T14%3A45%3A59.000Z%0A%0A%3C%2Fdetails%3E "This will take you to GitHub to file a new issue.") 1. [Glossary](https://developer.mozilla.org/en-US/docs/Glossary) 2. 1. [Abstraction](https://developer.mozilla.org/en-US/docs/Glossary/Abstraction) 2. [Accent](https://developer.mozilla.org/en-US/docs/Glossary/Accent) 3. [Accessibility](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility) 4. [Accessibility tree](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility_tree) 5. [Accessible description](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_description) 6. [Accessible name](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_name) 7. [Adobe Flash](https://developer.mozilla.org/en-US/docs/Glossary/Adobe_Flash) 8. [Advance measure](https://developer.mozilla.org/en-US/docs/Glossary/Advance_measure) 9. [Ajax](https://developer.mozilla.org/en-US/docs/Glossary/AJAX) 10. [Algorithm](https://developer.mozilla.org/en-US/docs/Glossary/Algorithm) 11. [Alignment container](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Container) 12. [Alignment subject](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Subject) 13. [Alpha (alpha channel)](https://developer.mozilla.org/en-US/docs/Glossary/Alpha) 14. [ALPN](https://developer.mozilla.org/en-US/docs/Glossary/ALPN) 15. [API](https://developer.mozilla.org/en-US/docs/Glossary/API) 16. [Apple Safari](https://developer.mozilla.org/en-US/docs/Glossary/Apple_Safari) 17. [Application context](https://developer.mozilla.org/en-US/docs/Glossary/Application_context) 18. [Argument](https://developer.mozilla.org/en-US/docs/Glossary/Argument) 19. [ARIA](https://developer.mozilla.org/en-US/docs/Glossary/ARIA) 20. [ARPA](https://developer.mozilla.org/en-US/docs/Glossary/ARPA) 21. [ARPANET](https://developer.mozilla.org/en-US/docs/Glossary/Arpanet) 22. [Array](https://developer.mozilla.org/en-US/docs/Glossary/Array) 23. [ASCII](https://developer.mozilla.org/en-US/docs/Glossary/ASCII) 24. [Aspect ratio](https://developer.mozilla.org/en-US/docs/Glossary/Aspect_ratio) 25. [Asynchronous](https://developer.mozilla.org/en-US/docs/Glossary/Asynchronous) 26. [ATAG](https://developer.mozilla.org/en-US/docs/Glossary/ATAG) 27. [Attribute](https://developer.mozilla.org/en-US/docs/Glossary/Attribute) 28. [Authentication](https://developer.mozilla.org/en-US/docs/Glossary/Authentication) 29. [Authenticator](https://developer.mozilla.org/en-US/docs/Glossary/Authenticator) 30. [Bandwidth](https://developer.mozilla.org/en-US/docs/Glossary/Bandwidth) 31. [Base64](https://developer.mozilla.org/en-US/docs/Glossary/Base64) 32. [Baseline](https://developer.mozilla.org/en-US/docs/Glossary/Baseline) 1. [Baseline (compatibility)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Compatibility) 2. [Baseline (typography)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Typography) 33. [BCP 47 language tag](https://developer.mozilla.org/en-US/docs/Glossary/BCP_47_language_tag) 34. [Beacon](https://developer.mozilla.org/en-US/docs/Glossary/Beacon) 35. [Bézier curve](https://developer.mozilla.org/en-US/docs/Glossary/Bezier_curve) 36. [bfcache](https://developer.mozilla.org/en-US/docs/Glossary/bfcache) 37. [BiDi](https://developer.mozilla.org/en-US/docs/Glossary/BiDi) 38. [BigInt](https://developer.mozilla.org/en-US/docs/Glossary/BigInt) 39. [Binding](https://developer.mozilla.org/en-US/docs/Glossary/Binding) 40. [Bitwise flags](https://developer.mozilla.org/en-US/docs/Glossary/Bitwise_flags) 41. [Blink](https://developer.mozilla.org/en-US/docs/Glossary/Blink) 42. [blink element (<blink> tag)](https://developer.mozilla.org/en-US/docs/Glossary/blink_element) 43. [Block](https://developer.mozilla.org/en-US/docs/Glossary/Block) 1. [Block (CSS)](https://developer.mozilla.org/en-US/docs/Glossary/Block/CSS) 2. [Block (scripting)](https://developer.mozilla.org/en-US/docs/Glossary/Block/Scripting) 44. [Block cipher mode of operation](https://developer.mozilla.org/en-US/docs/Glossary/Block_cipher_mode_of_operation) 45. [Block-level content](https://developer.mozilla.org/en-US/docs/Glossary/Block-level_content) 46. [Boolean](https://developer.mozilla.org/en-US/docs/Glossary/Boolean) 1. [Boolean (JavaScript)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/JavaScript) 2. [Boolean attribute (ARIA)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/ARIA) 3. [Boolean attribute (HTML)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/HTML) 47. [Bounding box](https://developer.mozilla.org/en-US/docs/Glossary/Bounding_box) 48. [Breadcrumb](https://developer.mozilla.org/en-US/docs/Glossary/Breadcrumb) 49. [Brotli


id: webp-glossary-mdn-20260505-0
file: data/developer.mozilla.org/en-US/docs/Glossary/WebP-0.md
category: reference
title: WebP - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/WebP
date_saved: 2026-05-05T05:49:08.945549+00:00
instance: kb-cron
parent: webp-glossary-mdn-20260505-0
summary:
* [Skip to main content](https://developer.mozilla.org/en-US/docs/Glossary/WebP#content) * [Skip to search](https://developer.mozilla.org/en-US/docs/Glossary/WebP#search) [ MDN ](https://developer.mozilla.org/en-US/) HTML [HTML: Markup language](https://developer.mozilla.org/en-US/docs/Web/HTML) HTML reference * [Elements](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements) * [Global attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes) * [Attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Attributes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference "See all HTML references") HTML guides * [Responsive images](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Responsive_images) * [HTML cheatsheet](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Cheatsheet) * [Date & time formats](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Date_and_time_formats) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides "See all HTML guides") Markup languages * [SVG](https://developer.mozilla.org/en-US/docs/Web/SVG) * [MathML](https://developer.mozilla.org/en-US/docs/Web/MathML) * [XML](https://developer.mozilla.org/en-US/docs/Web/XML) CSS [CSS: Styling language](https://developer.mozilla.org/en-US/docs/Web/CSS) CSS reference * [Properties](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties) * [Selectors](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors) * [At-rules](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/At-rules) * [Values](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference "See all CSS references") CSS guides * [Box model](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Box_model/Introduction) * [Animations](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Animations/Using) * [Flexbox](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Flexible_box_layout/Basic_concepts) * [Colors](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Colors/Applying_color) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides "See all CSS guides") Layout cookbook * [Column layouts](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Column_layouts) * [Centering an element](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Center_an_element) * [Card component](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Card) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook) JavaScriptJS [JavaScript: Scripting language](https://developer.mozilla.org/en-US/docs/Web/JavaScript) JS reference * [Standard built-in objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects) * [Expressions & operators](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators) * [Statements & declarations](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements) * [Functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference "See all JavaScript references") JS guides * [Control flow & error handing](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Control_flow_and_error_handling) * [Loops and iteration](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration) * [Working with objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_objects) * [Using classes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_classes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide "See all JavaScript guides") Web APIs [Web APIs: Programming interfaces](https://developer.mozilla.org/en-US/docs/Web/API) Web API reference * [File system API](https://developer.mozilla.org/en-US/docs/Web/API/File_System_API) * [Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) * [Geolocation API](https://developer.mozilla.org/en-US/docs/Web/API/Geolocation_API) * [HTML DOM API](https://developer.mozilla.org/en-US/docs/Web/API/HTML_DOM_API) * [Push API](https://developer.mozilla.org/en-US/docs/Web/API/Push_API) * [Service worker API](https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API) * [See all…](https://developer.mozilla.org/en-US/docs/Web/API


id: webp-glossary-mdn-20260505-1
file: data/developer.mozilla.org/en-US/docs/Glossary/WebP-1.md
category: reference
title: WebP - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/WebP
date_saved: 2026-05-05T05:49:08.945549+00:00
instance: kb-cron
parent: webp-glossary-mdn-20260505-0
summary:
## Help improve MDN [Learn how to contribute](https://developer.mozilla.org/en-US/docs/MDN/Community/Getting_started) This page was last modified on Aug 4, 2025 by [MDN contributors](https://developer.mozilla.org/en-US/docs/Glossary/WebP/contributors.txt). [View this page on GitHub](https://github.com/mdn/content/blob/main/files/en-us/glossary/webp/index.md?plain=1 "Folder: en-us/glossary/webp \(Opens in a new tab\)") • [Report a problem with this content](https://github.com/mdn/content/issues/new?template=page-report.yml&mdn-url=https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FWebP&metadata=%3C%21--+Do+not+make+changes+below+this+line+--%3E%0A%3Cdetails%3E%0A%3Csummary%3EPage+report+details%3C%2Fsummary%3E%0A%0A*+Folder%3A+%60en-us%2Fglossary%2Fwebp%60%0A*+MDN+URL%3A+https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FWebP%0A*+GitHub+URL%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fblob%2Fmain%2Ffiles%2Fen-us%2Fglossary%2Fwebp%2Findex.md%0A*+Last+commit%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fcommit%2F1ac2997717ee7e899121ab045cf5b391e1e15518%0A*+Document+last+modified%3A+2025-08-04T18%3A47%3A53.000Z%0A%0A%3C%2Fdetails%3E "This will take you to GitHub to file a new issue.") 1. [Glossary](https://developer.mozilla.org/en-US/docs/Glossary) 2. 1. [Abstraction](https://developer.mozilla.org/en-US/docs/Glossary/Abstraction) 2. [Accent](https://developer.mozilla.org/en-US/docs/Glossary/Accent) 3. [Accessibility](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility) 4. [Accessibility tree](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility_tree) 5. [Accessible description](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_description) 6. [Accessible name](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_name) 7. [Adobe Flash](https://developer.mozilla.org/en-US/docs/Glossary/Adobe_Flash) 8. [Advance measure](https://developer.mozilla.org/en-US/docs/Glossary/Advance_measure) 9. [Ajax](https://developer.mozilla.org/en-US/docs/Glossary/AJAX) 10. [Algorithm](https://developer.mozilla.org/en-US/docs/Glossary/Algorithm) 11. [Alignment container](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Container) 12. [Alignment subject](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Subject) 13. [Alpha (alpha channel)](https://developer.mozilla.org/en-US/docs/Glossary/Alpha) 14. [ALPN](https://developer.mozilla.org/en-US/docs/Glossary/ALPN) 15. [API](https://developer.mozilla.org/en-US/docs/Glossary/API) 16. [Apple Safari](https://developer.mozilla.org/en-US/docs/Glossary/Apple_Safari) 17. [Application context](https://developer.mozilla.org/en-US/docs/Glossary/Application_context) 18. [Argument](https://developer.mozilla.org/en-US/docs/Glossary/Argument) 19. [ARIA](https://developer.mozilla.org/en-US/docs/Glossary/ARIA) 20. [ARPA](https://developer.mozilla.org/en-US/docs/Glossary/ARPA) 21. [ARPANET](https://developer.mozilla.org/en-US/docs/Glossary/Arpanet) 22. [Array](https://developer.mozilla.org/en-US/docs/Glossary/Array) 23. [ASCII](https://developer.mozilla.org/en-US/docs/Glossary/ASCII) 24. [Aspect ratio](https://developer.mozilla.org/en-US/docs/Glossary/Aspect_ratio) 25. [Asynchronous](https://developer.mozilla.org/en-US/docs/Glossary/Asynchronous) 26. [ATAG](https://developer.mozilla.org/en-US/docs/Glossary/ATAG) 27. [Attribute](https://developer.mozilla.org/en-US/docs/Glossary/Attribute) 28. [Authentication](https://developer.mozilla.org/en-US/docs/Glossary/Authentication) 29. [Authenticator](https://developer.mozilla.org/en-US/docs/Glossary/Authenticator) 30. [Bandwidth](https://developer.mozilla.org/en-US/docs/Glossary/Bandwidth) 31. [Base64](https://developer.mozilla.org/en-US/docs/Glossary/Base64) 32. [Baseline](https://developer.mozilla.org/en-US/docs/Glossary/Baseline) 1. [Baseline (compatibility)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Compatibility) 2. [Baseline (typography)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Typography) 33. [BCP 47 language tag](https://developer.mozilla.org/en-US/docs/Glossary/BCP_47_language_tag) 34. [Beacon](https://developer.mozilla.org/en-US/docs/Glossary/Beacon) 35. [Bézier curve](https://developer.mozilla.org/en-US/docs/Glossary/Bezier_curve) 36. [bfcache](https://developer.mozilla.org/en-US/docs/Glossary/bfcache) 37. [BiDi](https://developer.mozilla.org/en-US/docs/Glossary/BiDi) 38. [BigInt](https://developer.mozilla.org/en-US/docs/Glossary/BigInt) 39. [Binding](https://developer.mozilla.org/en-US/docs/Glossary/Binding) 40. [Bitwise flags](https://developer.mozilla.org/en-US/docs/Glossary/Bitwise_flags) 41. [Blink](https://developer.mozilla.org/en-US/docs/Glossary/Blink) 42. [blink element (<blink> tag)](https://developer.mozilla.org/en-US/docs/Glossary/blink_element) 43. [Block](https://developer.mozilla.org/en-US/docs/Glossary/Block) 1. [Block (CSS)](https://developer.mozilla.org/en-US/docs/Glossary/Block/CSS) 2. [Block (scripting)](https://developer.mozilla.org/en-US/docs/Glossary/Block/Scripting) 44. [Block cipher mode of operation](https://developer.mozilla.org/en-US/docs/Glossary/Block_cipher_mode_of_operation) 45. [Block-level content](https://developer.mozilla.org/en-US/docs/Glossary/Block-level_content) 46. [Boolean](https://developer.mozilla.org/en-US/docs/Glossary/Boolean) 1. [Boolean (JavaScript)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/JavaScript) 2. [Boolean attribute (ARIA)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/ARIA) 3. [Boolean attribute (HTML)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/HTML) 47. [Bounding box](https://developer.mozilla.org/en-US/docs/Glossary/Bounding_box) 48. [Breadcrumb](https://developer.mozilla.org/en-US/docs/Glossary/Breadcrumb) 49. [Brotli


id: webrtc-glossary-mdn-20260505-0
file: data/developer.mozilla.org/en-US/docs/Glossary/WebRTC-0.md
category: reference
title: WebRTC - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/WebRTC
date_saved: 2026-05-05T05:49:11.433243+00:00
instance: kb-cron
parent: webrtc-glossary-mdn-20260505-0
summary:
* [Skip to main content](https://developer.mozilla.org/en-US/docs/Glossary/WebRTC#content) * [Skip to search](https://developer.mozilla.org/en-US/docs/Glossary/WebRTC#search) [ MDN ](https://developer.mozilla.org/en-US/) HTML [HTML: Markup language](https://developer.mozilla.org/en-US/docs/Web/HTML) HTML reference * [Elements](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements) * [Global attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes) * [Attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Attributes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference "See all HTML references") HTML guides * [Responsive images](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Responsive_images) * [HTML cheatsheet](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Cheatsheet) * [Date & time formats](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Date_and_time_formats) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides "See all HTML guides") Markup languages * [SVG](https://developer.mozilla.org/en-US/docs/Web/SVG) * [MathML](https://developer.mozilla.org/en-US/docs/Web/MathML) * [XML](https://developer.mozilla.org/en-US/docs/Web/XML) CSS [CSS: Styling language](https://developer.mozilla.org/en-US/docs/Web/CSS) CSS reference * [Properties](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties) * [Selectors](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors) * [At-rules](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/At-rules) * [Values](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference "See all CSS references") CSS guides * [Box model](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Box_model/Introduction) * [Animations](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Animations/Using) * [Flexbox](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Flexible_box_layout/Basic_concepts) * [Colors](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Colors/Applying_color) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides "See all CSS guides") Layout cookbook * [Column layouts](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Column_layouts) * [Centering an element](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Center_an_element) * [Card component](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Card) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook) JavaScriptJS [JavaScript: Scripting language](https://developer.mozilla.org/en-US/docs/Web/JavaScript) JS reference * [Standard built-in objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects) * [Expressions & operators](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators) * [Statements & declarations](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements) * [Functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference "See all JavaScript references") JS guides * [Control flow & error handing](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Control_flow_and_error_handling) * [Loops and iteration](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration) * [Working with objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_objects) * [Using classes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_classes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide "See all JavaScript guides") Web APIs [Web APIs: Programming interfaces](https://developer.mozilla.org/en-US/docs/Web/API) Web API reference * [File system API](https://developer.mozilla.org/en-US/docs/Web/API/File_System_API) * [Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) * [Geolocation API](https://developer.mozilla.org/en-US/docs/Web/API/Geolocation_API) * [HTML DOM API](https://developer.mozilla.org/en-US/docs/Web/API/HTML_DOM_API) * [Push API](https://developer.mozilla.org/en-US/docs/Web/API/Push_API) * [Service worker API](https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API) * [See all…](https://developer.mozilla.org/en-US/docs/Web/API


id: webrtc-glossary-mdn-20260505-1
file: data/developer.mozilla.org/en-US/docs/Glossary/WebRTC-1.md
category: reference
title: WebRTC - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/WebRTC
date_saved: 2026-05-05T05:49:11.433243+00:00
instance: kb-cron
parent: webrtc-glossary-mdn-20260505-0
summary:
## Help improve MDN [Learn how to contribute](https://developer.mozilla.org/en-US/docs/MDN/Community/Getting_started) This page was last modified on Jul 11, 2025 by [MDN contributors](https://developer.mozilla.org/en-US/docs/Glossary/WebRTC/contributors.txt). [View this page on GitHub](https://github.com/mdn/content/blob/main/files/en-us/glossary/webrtc/index.md?plain=1 "Folder: en-us/glossary/webrtc \(Opens in a new tab\)") • [Report a problem with this content](https://github.com/mdn/content/issues/new?template=page-report.yml&mdn-url=https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FWebRTC&metadata=%3C%21--+Do+not+make+changes+below+this+line+--%3E%0A%3Cdetails%3E%0A%3Csummary%3EPage+report+details%3C%2Fsummary%3E%0A%0A*+Folder%3A+%60en-us%2Fglossary%2Fwebrtc%60%0A*+MDN+URL%3A+https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FWebRTC%0A*+GitHub+URL%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fblob%2Fmain%2Ffiles%2Fen-us%2Fglossary%2Fwebrtc%2Findex.md%0A*+Last+commit%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fcommit%2F2547f622337d6cbf8c3794776b17ed377d6aad57%0A*+Document+last+modified%3A+2025-07-11T14%3A45%3A59.000Z%0A%0A%3C%2Fdetails%3E "This will take you to GitHub to file a new issue.") 1. [Glossary](https://developer.mozilla.org/en-US/docs/Glossary) 2. 1. [Abstraction](https://developer.mozilla.org/en-US/docs/Glossary/Abstraction) 2. [Accent](https://developer.mozilla.org/en-US/docs/Glossary/Accent) 3. [Accessibility](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility) 4. [Accessibility tree](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility_tree) 5. [Accessible description](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_description) 6. [Accessible name](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_name) 7. [Adobe Flash](https://developer.mozilla.org/en-US/docs/Glossary/Adobe_Flash) 8. [Advance measure](https://developer.mozilla.org/en-US/docs/Glossary/Advance_measure) 9. [Ajax](https://developer.mozilla.org/en-US/docs/Glossary/AJAX) 10. [Algorithm](https://developer.mozilla.org/en-US/docs/Glossary/Algorithm) 11. [Alignment container](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Container) 12. [Alignment subject](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Subject) 13. [Alpha (alpha channel)](https://developer.mozilla.org/en-US/docs/Glossary/Alpha) 14. [ALPN](https://developer.mozilla.org/en-US/docs/Glossary/ALPN) 15. [API](https://developer.mozilla.org/en-US/docs/Glossary/API) 16. [Apple Safari](https://developer.mozilla.org/en-US/docs/Glossary/Apple_Safari) 17. [Application context](https://developer.mozilla.org/en-US/docs/Glossary/Application_context) 18. [Argument](https://developer.mozilla.org/en-US/docs/Glossary/Argument) 19. [ARIA](https://developer.mozilla.org/en-US/docs/Glossary/ARIA) 20. [ARPA](https://developer.mozilla.org/en-US/docs/Glossary/ARPA) 21. [ARPANET](https://developer.mozilla.org/en-US/docs/Glossary/Arpanet) 22. [Array](https://developer.mozilla.org/en-US/docs/Glossary/Array) 23. [ASCII](https://developer.mozilla.org/en-US/docs/Glossary/ASCII) 24. [Aspect ratio](https://developer.mozilla.org/en-US/docs/Glossary/Aspect_ratio) 25. [Asynchronous](https://developer.mozilla.org/en-US/docs/Glossary/Asynchronous) 26. [ATAG](https://developer.mozilla.org/en-US/docs/Glossary/ATAG) 27. [Attribute](https://developer.mozilla.org/en-US/docs/Glossary/Attribute) 28. [Authentication](https://developer.mozilla.org/en-US/docs/Glossary/Authentication) 29. [Authenticator](https://developer.mozilla.org/en-US/docs/Glossary/Authenticator) 30. [Bandwidth](https://developer.mozilla.org/en-US/docs/Glossary/Bandwidth) 31. [Base64](https://developer.mozilla.org/en-US/docs/Glossary/Base64) 32. [Baseline](https://developer.mozilla.org/en-US/docs/Glossary/Baseline) 1. [Baseline (compatibility)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Compatibility) 2. [Baseline (typography)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Typography) 33. [BCP 47 language tag](https://developer.mozilla.org/en-US/docs/Glossary/BCP_47_language_tag) 34. [Beacon](https://developer.mozilla.org/en-US/docs/Glossary/Beacon) 35. [Bézier curve](https://developer.mozilla.org/en-US/docs/Glossary/Bezier_curve) 36. [bfcache](https://developer.mozilla.org/en-US/docs/Glossary/bfcache) 37. [BiDi](https://developer.mozilla.org/en-US/docs/Glossary/BiDi) 38. [BigInt](https://developer.mozilla.org/en-US/docs/Glossary/BigInt) 39. [Binding](https://developer.mozilla.org/en-US/docs/Glossary/Binding) 40. [Bitwise flags](https://developer.mozilla.org/en-US/docs/Glossary/Bitwise_flags) 41. [Blink](https://developer.mozilla.org/en-US/docs/Glossary/Blink) 42. [blink element (<blink> tag)](https://developer.mozilla.org/en-US/docs/Glossary/blink_element) 43. [Block](https://developer.mozilla.org/en-US/docs/Glossary/Block) 1. [Block (CSS)](https://developer.mozilla.org/en-US/docs/Glossary/Block/CSS) 2. [Block (scripting)](https://developer.mozilla.org/en-US/docs/Glossary/Block/Scripting) 44. [Block cipher mode of operation](https://developer.mozilla.org/en-US/docs/Glossary/Block_cipher_mode_of_operation) 45. [Block-level content](https://developer.mozilla.org/en-US/docs/Glossary/Block-level_content) 46. [Boolean](https://developer.mozilla.org/en-US/docs/Glossary/Boolean) 1. [Boolean (JavaScript)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/JavaScript) 2. [Boolean attribute (ARIA)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/ARIA) 3. [Boolean attribute (HTML)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/HTML) 47. [Bounding box](https://developer.mozilla.org/en-US/docs/Glossary/Bounding_box) 48. [Breadcrumb](https://developer.mozilla.org/en-US/docs/Glossary/Breadcrumb) 49. [Brotli


id: websockets-glossary-mdn-20260505-0
file: data/developer.mozilla.org/en-US/docs/Glossary/WebSockets-0.md
category: reference
title: WebSockets - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/WebSockets
date_saved: 2026-05-05T05:49:13.951753+00:00
instance: kb-cron
parent: websockets-glossary-mdn-20260505-0
summary:
* [Skip to main content](https://developer.mozilla.org/en-US/docs/Glossary/WebSockets#content) * [Skip to search](https://developer.mozilla.org/en-US/docs/Glossary/WebSockets#search) [ MDN ](https://developer.mozilla.org/en-US/) HTML [HTML: Markup language](https://developer.mozilla.org/en-US/docs/Web/HTML) HTML reference * [Elements](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements) * [Global attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes) * [Attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Attributes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference "See all HTML references") HTML guides * [Responsive images](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Responsive_images) * [HTML cheatsheet](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Cheatsheet) * [Date & time formats](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Date_and_time_formats) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides "See all HTML guides") Markup languages * [SVG](https://developer.mozilla.org/en-US/docs/Web/SVG) * [MathML](https://developer.mozilla.org/en-US/docs/Web/MathML) * [XML](https://developer.mozilla.org/en-US/docs/Web/XML) CSS [CSS: Styling language](https://developer.mozilla.org/en-US/docs/Web/CSS) CSS reference * [Properties](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties) * [Selectors](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors) * [At-rules](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/At-rules) * [Values](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference "See all CSS references") CSS guides * [Box model](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Box_model/Introduction) * [Animations](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Animations/Using) * [Flexbox](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Flexible_box_layout/Basic_concepts) * [Colors](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Colors/Applying_color) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides "See all CSS guides") Layout cookbook * [Column layouts](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Column_layouts) * [Centering an element](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Center_an_element) * [Card component](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Card) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook) JavaScriptJS [JavaScript: Scripting language](https://developer.mozilla.org/en-US/docs/Web/JavaScript) JS reference * [Standard built-in objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects) * [Expressions & operators](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators) * [Statements & declarations](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements) * [Functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference "See all JavaScript references") JS guides * [Control flow & error handing](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Control_flow_and_error_handling) * [Loops and iteration](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration) * [Working with objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_objects) * [Using classes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_classes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide "See all JavaScript guides") Web APIs [Web APIs: Programming interfaces](https://developer.mozilla.org/en-US/docs/Web/API) Web API reference * [File system API](https://developer.mozilla.org/en-US/docs/Web/API/File_System_API) * [Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) * [Geolocation API](https://developer.mozilla.org/en-US/docs/Web/API/Geolocation_API) * [HTML DOM API](https://developer.mozilla.org/en-US/docs/Web/API/HTML_DOM_API) * [Push API](https://developer.mozilla.org/en-US/docs/Web/API/Push_API) * [Service worker API](https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API) * [See all…](https://developer.mozilla.org/en-US/docs/Web/API


id: websockets-glossary-mdn-20260505-1
file: data/developer.mozilla.org/en-US/docs/Glossary/WebSockets-1.md
category: reference
title: WebSockets - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/WebSockets
date_saved: 2026-05-05T05:49:13.951753+00:00
instance: kb-cron
parent: websockets-glossary-mdn-20260505-0
summary:
## Help improve MDN [Learn how to contribute](https://developer.mozilla.org/en-US/docs/MDN/Community/Getting_started) This page was last modified on Jul 11, 2025 by [MDN contributors](https://developer.mozilla.org/en-US/docs/Glossary/WebSockets/contributors.txt). [View this page on GitHub](https://github.com/mdn/content/blob/main/files/en-us/glossary/websockets/index.md?plain=1 "Folder: en-us/glossary/websockets \(Opens in a new tab\)") • [Report a problem with this content](https://github.com/mdn/content/issues/new?template=page-report.yml&mdn-url=https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FWebSockets&metadata=%3C%21--+Do+not+make+changes+below+this+line+--%3E%0A%3Cdetails%3E%0A%3Csummary%3EPage+report+details%3C%2Fsummary%3E%0A%0A*+Folder%3A+%60en-us%2Fglossary%2Fwebsockets%60%0A*+MDN+URL%3A+https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FWebSockets%0A*+GitHub+URL%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fblob%2Fmain%2Ffiles%2Fen-us%2Fglossary%2Fwebsockets%2Findex.md%0A*+Last+commit%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fcommit%2F2547f622337d6cbf8c3794776b17ed377d6aad57%0A*+Document+last+modified%3A+2025-07-11T14%3A45%3A59.000Z%0A%0A%3C%2Fdetails%3E "This will take you to GitHub to file a new issue.") 1. [Glossary](https://developer.mozilla.org/en-US/docs/Glossary) 2. 1. [Abstraction](https://developer.mozilla.org/en-US/docs/Glossary/Abstraction) 2. [Accent](https://developer.mozilla.org/en-US/docs/Glossary/Accent) 3. [Accessibility](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility) 4. [Accessibility tree](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility_tree) 5. [Accessible description](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_description) 6. [Accessible name](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_name) 7. [Adobe Flash](https://developer.mozilla.org/en-US/docs/Glossary/Adobe_Flash) 8. [Advance measure](https://developer.mozilla.org/en-US/docs/Glossary/Advance_measure) 9. [Ajax](https://developer.mozilla.org/en-US/docs/Glossary/AJAX) 10. [Algorithm](https://developer.mozilla.org/en-US/docs/Glossary/Algorithm) 11. [Alignment container](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Container) 12. [Alignment subject](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Subject) 13. [Alpha (alpha channel)](https://developer.mozilla.org/en-US/docs/Glossary/Alpha) 14. [ALPN](https://developer.mozilla.org/en-US/docs/Glossary/ALPN) 15. [API](https://developer.mozilla.org/en-US/docs/Glossary/API) 16. [Apple Safari](https://developer.mozilla.org/en-US/docs/Glossary/Apple_Safari) 17. [Application context](https://developer.mozilla.org/en-US/docs/Glossary/Application_context) 18. [Argument](https://developer.mozilla.org/en-US/docs/Glossary/Argument) 19. [ARIA](https://developer.mozilla.org/en-US/docs/Glossary/ARIA) 20. [ARPA](https://developer.mozilla.org/en-US/docs/Glossary/ARPA) 21. [ARPANET](https://developer.mozilla.org/en-US/docs/Glossary/Arpanet) 22. [Array](https://developer.mozilla.org/en-US/docs/Glossary/Array) 23. [ASCII](https://developer.mozilla.org/en-US/docs/Glossary/ASCII) 24. [Aspect ratio](https://developer.mozilla.org/en-US/docs/Glossary/Aspect_ratio) 25. [Asynchronous](https://developer.mozilla.org/en-US/docs/Glossary/Asynchronous) 26. [ATAG](https://developer.mozilla.org/en-US/docs/Glossary/ATAG) 27. [Attribute](https://developer.mozilla.org/en-US/docs/Glossary/Attribute) 28. [Authentication](https://developer.mozilla.org/en-US/docs/Glossary/Authentication) 29. [Authenticator](https://developer.mozilla.org/en-US/docs/Glossary/Authenticator) 30. [Bandwidth](https://developer.mozilla.org/en-US/docs/Glossary/Bandwidth) 31. [Base64](https://developer.mozilla.org/en-US/docs/Glossary/Base64) 32. [Baseline](https://developer.mozilla.org/en-US/docs/Glossary/Baseline) 1. [Baseline (compatibility)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Compatibility) 2. [Baseline (typography)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Typography) 33. [BCP 47 language tag](https://developer.mozilla.org/en-US/docs/Glossary/BCP_47_language_tag) 34. [Beacon](https://developer.mozilla.org/en-US/docs/Glossary/Beacon) 35. [Bézier curve](https://developer.mozilla.org/en-US/docs/Glossary/Bezier_curve) 36. [bfcache](https://developer.mozilla.org/en-US/docs/Glossary/bfcache) 37. [BiDi](https://developer.mozilla.org/en-US/docs/Glossary/BiDi) 38. [BigInt](https://developer.mozilla.org/en-US/docs/Glossary/BigInt) 39. [Binding](https://developer.mozilla.org/en-US/docs/Glossary/Binding) 40. [Bitwise flags](https://developer.mozilla.org/en-US/docs/Glossary/Bitwise_flags) 41. [Blink](https://developer.mozilla.org/en-US/docs/Glossary/Blink) 42. [blink element (<blink> tag)](https://developer.mozilla.org/en-US/docs/Glossary/blink_element) 43. [Block](https://developer.mozilla.org/en-US/docs/Glossary/Block) 1. [Block (CSS)](https://developer.mozilla.org/en-US/docs/Glossary/Block/CSS) 2. [Block (scripting)](https://developer.mozilla.org/en-US/docs/Glossary/Block/Scripting) 44. [Block cipher mode of operation](https://developer.mozilla.org/en-US/docs/Glossary/Block_cipher_mode_of_operation) 45. [Block-level content](https://developer.mozilla.org/en-US/docs/Glossary/Block-level_content) 46. [Boolean](https://developer.mozilla.org/en-US/docs/Glossary/Boolean) 1. [Boolean (JavaScript)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/JavaScript) 2. [Boolean attribute (ARIA)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/ARIA) 3. [Boolean attribute (HTML)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/HTML) 47. [Bounding box](https://developer.mozilla.org/en-US/docs/Glossary/Bounding_box) 48. [Breadcrumb](https://developer.mozilla.org/en-US/docs/Glossary/Breadcrumb) 49. [Brotli


id: webvtt-glossary-mdn-20260505-0
file: data/developer.mozilla.org/en-US/docs/Glossary/WebVTT-0.md
category: reference
title: WebVTT - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/WebVTT
date_saved: 2026-05-05T05:49:16.480385+00:00
instance: kb-cron
parent: webvtt-glossary-mdn-20260505-0
summary:
* [Skip to main content](https://developer.mozilla.org/en-US/docs/Glossary/WebVTT#content) * [Skip to search](https://developer.mozilla.org/en-US/docs/Glossary/WebVTT#search) [ MDN ](https://developer.mozilla.org/en-US/) HTML [HTML: Markup language](https://developer.mozilla.org/en-US/docs/Web/HTML) HTML reference * [Elements](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements) * [Global attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes) * [Attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Attributes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference "See all HTML references") HTML guides * [Responsive images](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Responsive_images) * [HTML cheatsheet](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Cheatsheet) * [Date & time formats](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Date_and_time_formats) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides "See all HTML guides") Markup languages * [SVG](https://developer.mozilla.org/en-US/docs/Web/SVG) * [MathML](https://developer.mozilla.org/en-US/docs/Web/MathML) * [XML](https://developer.mozilla.org/en-US/docs/Web/XML) CSS [CSS: Styling language](https://developer.mozilla.org/en-US/docs/Web/CSS) CSS reference * [Properties](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties) * [Selectors](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors) * [At-rules](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/At-rules) * [Values](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference "See all CSS references") CSS guides * [Box model](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Box_model/Introduction) * [Animations](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Animations/Using) * [Flexbox](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Flexible_box_layout/Basic_concepts) * [Colors](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Colors/Applying_color) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides "See all CSS guides") Layout cookbook * [Column layouts](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Column_layouts) * [Centering an element](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Center_an_element) * [Card component](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Card) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook) JavaScriptJS [JavaScript: Scripting language](https://developer.mozilla.org/en-US/docs/Web/JavaScript) JS reference * [Standard built-in objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects) * [Expressions & operators](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators) * [Statements & declarations](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements) * [Functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference "See all JavaScript references") JS guides * [Control flow & error handing](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Control_flow_and_error_handling) * [Loops and iteration](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration) * [Working with objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_objects) * [Using classes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_classes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide "See all JavaScript guides") Web APIs [Web APIs: Programming interfaces](https://developer.mozilla.org/en-US/docs/Web/API) Web API reference * [File system API](https://developer.mozilla.org/en-US/docs/Web/API/File_System_API) * [Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) * [Geolocation API](https://developer.mozilla.org/en-US/docs/Web/API/Geolocation_API) * [HTML DOM API](https://developer.mozilla.org/en-US/docs/Web/API/HTML_DOM_API) * [Push API](https://developer.mozilla.org/en-US/docs/Web/API/Push_API) * [Service worker API](https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API) * [See all…](https://developer.mozilla.org/en-US/docs/Web/API


id: webvtt-glossary-mdn-20260505-1
file: data/developer.mozilla.org/en-US/docs/Glossary/WebVTT-1.md
category: reference
title: WebVTT - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/WebVTT
date_saved: 2026-05-05T05:49:16.480385+00:00
instance: kb-cron
parent: webvtt-glossary-mdn-20260505-0
summary:
## Help improve MDN [Learn how to contribute](https://developer.mozilla.org/en-US/docs/MDN/Community/Getting_started) This page was last modified on Jul 11, 2025 by [MDN contributors](https://developer.mozilla.org/en-US/docs/Glossary/WebVTT/contributors.txt). [View this page on GitHub](https://github.com/mdn/content/blob/main/files/en-us/glossary/webvtt/index.md?plain=1 "Folder: en-us/glossary/webvtt \(Opens in a new tab\)") • [Report a problem with this content](https://github.com/mdn/content/issues/new?template=page-report.yml&mdn-url=https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FWebVTT&metadata=%3C%21--+Do+not+make+changes+below+this+line+--%3E%0A%3Cdetails%3E%0A%3Csummary%3EPage+report+details%3C%2Fsummary%3E%0A%0A*+Folder%3A+%60en-us%2Fglossary%2Fwebvtt%60%0A*+MDN+URL%3A+https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FWebVTT%0A*+GitHub+URL%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fblob%2Fmain%2Ffiles%2Fen-us%2Fglossary%2Fwebvtt%2Findex.md%0A*+Last+commit%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fcommit%2F2547f622337d6cbf8c3794776b17ed377d6aad57%0A*+Document+last+modified%3A+2025-07-11T14%3A45%3A59.000Z%0A%0A%3C%2Fdetails%3E "This will take you to GitHub to file a new issue.") 1. [Glossary](https://developer.mozilla.org/en-US/docs/Glossary) 2. 1. [Abstraction](https://developer.mozilla.org/en-US/docs/Glossary/Abstraction) 2. [Accent](https://developer.mozilla.org/en-US/docs/Glossary/Accent) 3. [Accessibility](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility) 4. [Accessibility tree](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility_tree) 5. [Accessible description](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_description) 6. [Accessible name](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_name) 7. [Adobe Flash](https://developer.mozilla.org/en-US/docs/Glossary/Adobe_Flash) 8. [Advance measure](https://developer.mozilla.org/en-US/docs/Glossary/Advance_measure) 9. [Ajax](https://developer.mozilla.org/en-US/docs/Glossary/AJAX) 10. [Algorithm](https://developer.mozilla.org/en-US/docs/Glossary/Algorithm) 11. [Alignment container](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Container) 12. [Alignment subject](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Subject) 13. [Alpha (alpha channel)](https://developer.mozilla.org/en-US/docs/Glossary/Alpha) 14. [ALPN](https://developer.mozilla.org/en-US/docs/Glossary/ALPN) 15. [API](https://developer.mozilla.org/en-US/docs/Glossary/API) 16. [Apple Safari](https://developer.mozilla.org/en-US/docs/Glossary/Apple_Safari) 17. [Application context](https://developer.mozilla.org/en-US/docs/Glossary/Application_context) 18. [Argument](https://developer.mozilla.org/en-US/docs/Glossary/Argument) 19. [ARIA](https://developer.mozilla.org/en-US/docs/Glossary/ARIA) 20. [ARPA](https://developer.mozilla.org/en-US/docs/Glossary/ARPA) 21. [ARPANET](https://developer.mozilla.org/en-US/docs/Glossary/Arpanet) 22. [Array](https://developer.mozilla.org/en-US/docs/Glossary/Array) 23. [ASCII](https://developer.mozilla.org/en-US/docs/Glossary/ASCII) 24. [Aspect ratio](https://developer.mozilla.org/en-US/docs/Glossary/Aspect_ratio) 25. [Asynchronous](https://developer.mozilla.org/en-US/docs/Glossary/Asynchronous) 26. [ATAG](https://developer.mozilla.org/en-US/docs/Glossary/ATAG) 27. [Attribute](https://developer.mozilla.org/en-US/docs/Glossary/Attribute) 28. [Authentication](https://developer.mozilla.org/en-US/docs/Glossary/Authentication) 29. [Authenticator](https://developer.mozilla.org/en-US/docs/Glossary/Authenticator) 30. [Bandwidth](https://developer.mozilla.org/en-US/docs/Glossary/Bandwidth) 31. [Base64](https://developer.mozilla.org/en-US/docs/Glossary/Base64) 32. [Baseline](https://developer.mozilla.org/en-US/docs/Glossary/Baseline) 1. [Baseline (compatibility)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Compatibility) 2. [Baseline (typography)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Typography) 33. [BCP 47 language tag](https://developer.mozilla.org/en-US/docs/Glossary/BCP_47_language_tag) 34. [Beacon](https://developer.mozilla.org/en-US/docs/Glossary/Beacon) 35. [Bézier curve](https://developer.mozilla.org/en-US/docs/Glossary/Bezier_curve) 36. [bfcache](https://developer.mozilla.org/en-US/docs/Glossary/bfcache) 37. [BiDi](https://developer.mozilla.org/en-US/docs/Glossary/BiDi) 38. [BigInt](https://developer.mozilla.org/en-US/docs/Glossary/BigInt) 39. [Binding](https://developer.mozilla.org/en-US/docs/Glossary/Binding) 40. [Bitwise flags](https://developer.mozilla.org/en-US/docs/Glossary/Bitwise_flags) 41. [Blink](https://developer.mozilla.org/en-US/docs/Glossary/Blink) 42. [blink element (<blink> tag)](https://developer.mozilla.org/en-US/docs/Glossary/blink_element) 43. [Block](https://developer.mozilla.org/en-US/docs/Glossary/Block) 1. [Block (CSS)](https://developer.mozilla.org/en-US/docs/Glossary/Block/CSS) 2. [Block (scripting)](https://developer.mozilla.org/en-US/docs/Glossary/Block/Scripting) 44. [Block cipher mode of operation](https://developer.mozilla.org/en-US/docs/Glossary/Block_cipher_mode_of_operation) 45. [Block-level content](https://developer.mozilla.org/en-US/docs/Glossary/Block-level_content) 46. [Boolean](https://developer.mozilla.org/en-US/docs/Glossary/Boolean) 1. [Boolean (JavaScript)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/JavaScript) 2. [Boolean attribute (ARIA)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/ARIA) 3. [Boolean attribute (HTML)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/HTML) 47. [Bounding box](https://developer.mozilla.org/en-US/docs/Glossary/Bounding_box) 48. [Breadcrumb](https://developer.mozilla.org/en-US/docs/Glossary/Breadcrumb) 49. [Brotli


id: web-performance-glossary-mdn-20260505-0
file: data/developer.mozilla.org/en-US/docs/Glossary/Web_performance-0.md
category: reference
title: Web performance - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/Web_performance
date_saved: 2026-05-05T05:49:18.717759+00:00
instance: kb-cron
parent: web-performance-glossary-mdn-20260505-0
summary:
* [Skip to main content](https://developer.mozilla.org/en-US/docs/Glossary/Web_performance#content) * [Skip to search](https://developer.mozilla.org/en-US/docs/Glossary/Web_performance#search) [ MDN ](https://developer.mozilla.org/en-US/) HTML [HTML: Markup language](https://developer.mozilla.org/en-US/docs/Web/HTML) HTML reference * [Elements](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements) * [Global attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes) * [Attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Attributes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference "See all HTML references") HTML guides * [Responsive images](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Responsive_images) * [HTML cheatsheet](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Cheatsheet) * [Date & time formats](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Date_and_time_formats) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides "See all HTML guides") Markup languages * [SVG](https://developer.mozilla.org/en-US/docs/Web/SVG) * [MathML](https://developer.mozilla.org/en-US/docs/Web/MathML) * [XML](https://developer.mozilla.org/en-US/docs/Web/XML) CSS [CSS: Styling language](https://developer.mozilla.org/en-US/docs/Web/CSS) CSS reference * [Properties](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties) * [Selectors](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors) * [At-rules](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/At-rules) * [Values](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference "See all CSS references") CSS guides * [Box model](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Box_model/Introduction) * [Animations](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Animations/Using) * [Flexbox](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Flexible_box_layout/Basic_concepts) * [Colors](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Colors/Applying_color) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides "See all CSS guides") Layout cookbook * [Column layouts](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Column_layouts) * [Centering an element](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Center_an_element) * [Card component](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Card) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook) JavaScriptJS [JavaScript: Scripting language](https://developer.mozilla.org/en-US/docs/Web/JavaScript) JS reference * [Standard built-in objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects) * [Expressions & operators](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators) * [Statements & declarations](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements) * [Functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference "See all JavaScript references") JS guides * [Control flow & error handing](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Control_flow_and_error_handling) * [Loops and iteration](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration) * [Working with objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_objects) * [Using classes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_classes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide "See all JavaScript guides") Web APIs [Web APIs: Programming interfaces](https://developer.mozilla.org/en-US/docs/Web/API) Web API reference * [File system API](https://developer.mozilla.org/en-US/docs/Web/API/File_System_API) * [Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) * [Geolocation API](https://developer.mozilla.org/en-US/docs/Web/API/Geolocation_API) * [HTML DOM API](https://developer.mozilla.org/en-US/docs/Web/API/HTML_DOM_API) * [Push API](https://developer.mozilla.org/en-US/docs/Web/API/Push_API) * [Service worker API](https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API) * [See all…](https://developer.mozilla.org/en-US/docs/Web/API


id: web-performance-glossary-mdn-20260505-1
file: data/developer.mozilla.org/en-US/docs/Glossary/Web_performance-1.md
category: reference
title: Web performance - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/Web_performance
date_saved: 2026-05-05T05:49:18.717759+00:00
instance: kb-cron
parent: web-performance-glossary-mdn-20260505-0
summary:
## Help improve MDN [Learn how to contribute](https://developer.mozilla.org/en-US/docs/MDN/Community/Getting_started) This page was last modified on Jul 11, 2025 by [MDN contributors](https://developer.mozilla.org/en-US/docs/Glossary/Web_performance/contributors.txt). [View this page on GitHub](https://github.com/mdn/content/blob/main/files/en-us/glossary/web_performance/index.md?plain=1 "Folder: en-us/glossary/web_performance \(Opens in a new tab\)") • [Report a problem with this content](https://github.com/mdn/content/issues/new?template=page-report.yml&mdn-url=https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FWeb_performance&metadata=%3C%21--+Do+not+make+changes+below+this+line+--%3E%0A%3Cdetails%3E%0A%3Csummary%3EPage+report+details%3C%2Fsummary%3E%0A%0A*+Folder%3A+%60en-us%2Fglossary%2Fweb_performance%60%0A*+MDN+URL%3A+https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FWeb_performance%0A*+GitHub+URL%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fblob%2Fmain%2Ffiles%2Fen-us%2Fglossary%2Fweb_performance%2Findex.md%0A*+Last+commit%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fcommit%2F2547f622337d6cbf8c3794776b17ed377d6aad57%0A*+Document+last+modified%3A+2025-07-11T14%3A45%3A59.000Z%0A%0A%3C%2Fdetails%3E "This will take you to GitHub to file a new issue.") 1. [Glossary](https://developer.mozilla.org/en-US/docs/Glossary) 2. 1. [Abstraction](https://developer.mozilla.org/en-US/docs/Glossary/Abstraction) 2. [Accent](https://developer.mozilla.org/en-US/docs/Glossary/Accent) 3. [Accessibility](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility) 4. [Accessibility tree](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility_tree) 5. [Accessible description](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_description) 6. [Accessible name](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_name) 7. [Adobe Flash](https://developer.mozilla.org/en-US/docs/Glossary/Adobe_Flash) 8. [Advance measure](https://developer.mozilla.org/en-US/docs/Glossary/Advance_measure) 9. [Ajax](https://developer.mozilla.org/en-US/docs/Glossary/AJAX) 10. [Algorithm](https://developer.mozilla.org/en-US/docs/Glossary/Algorithm) 11. [Alignment container](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Container) 12. [Alignment subject](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Subject) 13. [Alpha (alpha channel)](https://developer.mozilla.org/en-US/docs/Glossary/Alpha) 14. [ALPN](https://developer.mozilla.org/en-US/docs/Glossary/ALPN) 15. [API](https://developer.mozilla.org/en-US/docs/Glossary/API) 16. [Apple Safari](https://developer.mozilla.org/en-US/docs/Glossary/Apple_Safari) 17. [Application context](https://developer.mozilla.org/en-US/docs/Glossary/Application_context) 18. [Argument](https://developer.mozilla.org/en-US/docs/Glossary/Argument) 19. [ARIA](https://developer.mozilla.org/en-US/docs/Glossary/ARIA) 20. [ARPA](https://developer.mozilla.org/en-US/docs/Glossary/ARPA) 21. [ARPANET](https://developer.mozilla.org/en-US/docs/Glossary/Arpanet) 22. [Array](https://developer.mozilla.org/en-US/docs/Glossary/Array) 23. [ASCII](https://developer.mozilla.org/en-US/docs/Glossary/ASCII) 24. [Aspect ratio](https://developer.mozilla.org/en-US/docs/Glossary/Aspect_ratio) 25. [Asynchronous](https://developer.mozilla.org/en-US/docs/Glossary/Asynchronous) 26. [ATAG](https://developer.mozilla.org/en-US/docs/Glossary/ATAG) 27. [Attribute](https://developer.mozilla.org/en-US/docs/Glossary/Attribute) 28. [Authentication](https://developer.mozilla.org/en-US/docs/Glossary/Authentication) 29. [Authenticator](https://developer.mozilla.org/en-US/docs/Glossary/Authenticator) 30. [Bandwidth](https://developer.mozilla.org/en-US/docs/Glossary/Bandwidth) 31. [Base64](https://developer.mozilla.org/en-US/docs/Glossary/Base64) 32. [Baseline](https://developer.mozilla.org/en-US/docs/Glossary/Baseline) 1. [Baseline (compatibility)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Compatibility) 2. [Baseline (typography)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Typography) 33. [BCP 47 language tag](https://developer.mozilla.org/en-US/docs/Glossary/BCP_47_language_tag) 34. [Beacon](https://developer.mozilla.org/en-US/docs/Glossary/Beacon) 35. [Bézier curve](https://developer.mozilla.org/en-US/docs/Glossary/Bezier_curve) 36. [bfcache](https://developer.mozilla.org/en-US/docs/Glossary/bfcache) 37. [BiDi](https://developer.mozilla.org/en-US/docs/Glossary/BiDi) 38. [BigInt](https://developer.mozilla.org/en-US/docs/Glossary/BigInt) 39. [Binding](https://developer.mozilla.org/en-US/docs/Glossary/Binding) 40. [Bitwise flags](https://developer.mozilla.org/en-US/docs/Glossary/Bitwise_flags) 41. [Blink](https://developer.mozilla.org/en-US/docs/Glossary/Blink) 42. [blink element (<blink> tag)](https://developer.mozilla.org/en-US/docs/Glossary/blink_element) 43. [Block](https://developer.mozilla.org/en-US/docs/Glossary/Block) 1. [Block (CSS)](https://developer.mozilla.org/en-US/docs/Glossary/Block/CSS) 2. [Block (scripting)](https://developer.mozilla.org/en-US/docs/Glossary/Block/Scripting) 44. [Block cipher mode of operation](https://developer.mozilla.org/en-US/docs/Glossary/Block_cipher_mode_of_operation) 45. [Block-level content](https://developer.mozilla.org/en-US/docs/Glossary/Block-level_content) 46. [Boolean](https://developer.mozilla.org/en-US/docs/Glossary/Boolean) 1. [Boolean (JavaScript)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/JavaScript) 2. [Boolean attribute (ARIA)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/ARIA) 3. [Boolean attribute (HTML)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/HTML) 47. [Bounding box](https://developer.mozilla.org/en-US/docs/Glossary/Bounding_box) 48. [Breadcrumb](https://developer.mozilla.org/en-US/docs/Glossary/Breadcrumb) 49. [Brotli


id: web-server-glossary-mdn-20260505-0
file: data/developer.mozilla.org/en-US/docs/Glossary/Web_server-0.md
category: reference
title: Web server - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/Web_server
date_saved: 2026-05-05T05:49:21.374673+00:00
instance: kb-cron
parent: web-server-glossary-mdn-20260505-0
summary:
* [Skip to main content](https://developer.mozilla.org/en-US/docs/Glossary/Web_server#content) * [Skip to search](https://developer.mozilla.org/en-US/docs/Glossary/Web_server#search) [ MDN ](https://developer.mozilla.org/en-US/) HTML [HTML: Markup language](https://developer.mozilla.org/en-US/docs/Web/HTML) HTML reference * [Elements](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements) * [Global attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes) * [Attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Attributes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference "See all HTML references") HTML guides * [Responsive images](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Responsive_images) * [HTML cheatsheet](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Cheatsheet) * [Date & time formats](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Date_and_time_formats) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides "See all HTML guides") Markup languages * [SVG](https://developer.mozilla.org/en-US/docs/Web/SVG) * [MathML](https://developer.mozilla.org/en-US/docs/Web/MathML) * [XML](https://developer.mozilla.org/en-US/docs/Web/XML) CSS [CSS: Styling language](https://developer.mozilla.org/en-US/docs/Web/CSS) CSS reference * [Properties](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties) * [Selectors](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors) * [At-rules](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/At-rules) * [Values](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference "See all CSS references") CSS guides * [Box model](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Box_model/Introduction) * [Animations](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Animations/Using) * [Flexbox](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Flexible_box_layout/Basic_concepts) * [Colors](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Colors/Applying_color) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides "See all CSS guides") Layout cookbook * [Column layouts](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Column_layouts) * [Centering an element](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Center_an_element) * [Card component](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Card) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook) JavaScriptJS [JavaScript: Scripting language](https://developer.mozilla.org/en-US/docs/Web/JavaScript) JS reference * [Standard built-in objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects) * [Expressions & operators](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators) * [Statements & declarations](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements) * [Functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference "See all JavaScript references") JS guides * [Control flow & error handing](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Control_flow_and_error_handling) * [Loops and iteration](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration) * [Working with objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_objects) * [Using classes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_classes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide "See all JavaScript guides") Web APIs [Web APIs: Programming interfaces](https://developer.mozilla.org/en-US/docs/Web/API) Web API reference * [File system API](https://developer.mozilla.org/en-US/docs/Web/API/File_System_API) * [Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) * [Geolocation API](https://developer.mozilla.org/en-US/docs/Web/API/Geolocation_API) * [HTML DOM API](https://developer.mozilla.org/en-US/docs/Web/API/HTML_DOM_API) * [Push API](https://developer.mozilla.org/en-US/docs/Web/API/Push_API) * [Service worker API](https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API) * [See all…](https://developer.mozilla.org/en-US/docs/Web/API


id: web-server-glossary-mdn-20260505-1
file: data/developer.mozilla.org/en-US/docs/Glossary/Web_server-1.md
category: reference
title: Web server - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/Web_server
date_saved: 2026-05-05T05:49:21.374673+00:00
instance: kb-cron
parent: web-server-glossary-mdn-20260505-0
summary:
## Help improve MDN [Learn how to contribute](https://developer.mozilla.org/en-US/docs/MDN/Community/Getting_started) This page was last modified on Jul 11, 2025 by [MDN contributors](https://developer.mozilla.org/en-US/docs/Glossary/Web_server/contributors.txt). [View this page on GitHub](https://github.com/mdn/content/blob/main/files/en-us/glossary/web_server/index.md?plain=1 "Folder: en-us/glossary/web_server \(Opens in a new tab\)") • [Report a problem with this content](https://github.com/mdn/content/issues/new?template=page-report.yml&mdn-url=https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FWeb_server&metadata=%3C%21--+Do+not+make+changes+below+this+line+--%3E%0A%3Cdetails%3E%0A%3Csummary%3EPage+report+details%3C%2Fsummary%3E%0A%0A*+Folder%3A+%60en-us%2Fglossary%2Fweb_server%60%0A*+MDN+URL%3A+https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FWeb_server%0A*+GitHub+URL%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fblob%2Fmain%2Ffiles%2Fen-us%2Fglossary%2Fweb_server%2Findex.md%0A*+Last+commit%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fcommit%2F2547f622337d6cbf8c3794776b17ed377d6aad57%0A*+Document+last+modified%3A+2025-07-11T14%3A45%3A59.000Z%0A%0A%3C%2Fdetails%3E "This will take you to GitHub to file a new issue.") 1. [Glossary](https://developer.mozilla.org/en-US/docs/Glossary) 2. 1. [Abstraction](https://developer.mozilla.org/en-US/docs/Glossary/Abstraction) 2. [Accent](https://developer.mozilla.org/en-US/docs/Glossary/Accent) 3. [Accessibility](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility) 4. [Accessibility tree](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility_tree) 5. [Accessible description](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_description) 6. [Accessible name](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_name) 7. [Adobe Flash](https://developer.mozilla.org/en-US/docs/Glossary/Adobe_Flash) 8. [Advance measure](https://developer.mozilla.org/en-US/docs/Glossary/Advance_measure) 9. [Ajax](https://developer.mozilla.org/en-US/docs/Glossary/AJAX) 10. [Algorithm](https://developer.mozilla.org/en-US/docs/Glossary/Algorithm) 11. [Alignment container](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Container) 12. [Alignment subject](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Subject) 13. [Alpha (alpha channel)](https://developer.mozilla.org/en-US/docs/Glossary/Alpha) 14. [ALPN](https://developer.mozilla.org/en-US/docs/Glossary/ALPN) 15. [API](https://developer.mozilla.org/en-US/docs/Glossary/API) 16. [Apple Safari](https://developer.mozilla.org/en-US/docs/Glossary/Apple_Safari) 17. [Application context](https://developer.mozilla.org/en-US/docs/Glossary/Application_context) 18. [Argument](https://developer.mozilla.org/en-US/docs/Glossary/Argument) 19. [ARIA](https://developer.mozilla.org/en-US/docs/Glossary/ARIA) 20. [ARPA](https://developer.mozilla.org/en-US/docs/Glossary/ARPA) 21. [ARPANET](https://developer.mozilla.org/en-US/docs/Glossary/Arpanet) 22. [Array](https://developer.mozilla.org/en-US/docs/Glossary/Array) 23. [ASCII](https://developer.mozilla.org/en-US/docs/Glossary/ASCII) 24. [Aspect ratio](https://developer.mozilla.org/en-US/docs/Glossary/Aspect_ratio) 25. [Asynchronous](https://developer.mozilla.org/en-US/docs/Glossary/Asynchronous) 26. [ATAG](https://developer.mozilla.org/en-US/docs/Glossary/ATAG) 27. [Attribute](https://developer.mozilla.org/en-US/docs/Glossary/Attribute) 28. [Authentication](https://developer.mozilla.org/en-US/docs/Glossary/Authentication) 29. [Authenticator](https://developer.mozilla.org/en-US/docs/Glossary/Authenticator) 30. [Bandwidth](https://developer.mozilla.org/en-US/docs/Glossary/Bandwidth) 31. [Base64](https://developer.mozilla.org/en-US/docs/Glossary/Base64) 32. [Baseline](https://developer.mozilla.org/en-US/docs/Glossary/Baseline) 1. [Baseline (compatibility)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Compatibility) 2. [Baseline (typography)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Typography) 33. [BCP 47 language tag](https://developer.mozilla.org/en-US/docs/Glossary/BCP_47_language_tag) 34. [Beacon](https://developer.mozilla.org/en-US/docs/Glossary/Beacon) 35. [Bézier curve](https://developer.mozilla.org/en-US/docs/Glossary/Bezier_curve) 36. [bfcache](https://developer.mozilla.org/en-US/docs/Glossary/bfcache) 37. [BiDi](https://developer.mozilla.org/en-US/docs/Glossary/BiDi) 38. [BigInt](https://developer.mozilla.org/en-US/docs/Glossary/BigInt) 39. [Binding](https://developer.mozilla.org/en-US/docs/Glossary/Binding) 40. [Bitwise flags](https://developer.mozilla.org/en-US/docs/Glossary/Bitwise_flags) 41. [Blink](https://developer.mozilla.org/en-US/docs/Glossary/Blink) 42. [blink element (<blink> tag)](https://developer.mozilla.org/en-US/docs/Glossary/blink_element) 43. [Block](https://developer.mozilla.org/en-US/docs/Glossary/Block) 1. [Block (CSS)](https://developer.mozilla.org/en-US/docs/Glossary/Block/CSS) 2. [Block (scripting)](https://developer.mozilla.org/en-US/docs/Glossary/Block/Scripting) 44. [Block cipher mode of operation](https://developer.mozilla.org/en-US/docs/Glossary/Block_cipher_mode_of_operation) 45. [Block-level content](https://developer.mozilla.org/en-US/docs/Glossary/Block-level_content) 46. [Boolean](https://developer.mozilla.org/en-US/docs/Glossary/Boolean) 1. [Boolean (JavaScript)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/JavaScript) 2. [Boolean attribute (ARIA)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/ARIA) 3. [Boolean attribute (HTML)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/HTML) 47. [Bounding box](https://developer.mozilla.org/en-US/docs/Glossary/Bounding_box) 48. [Breadcrumb](https://developer.mozilla.org/en-US/docs/Glossary/Breadcrumb) 49. [Brotli


id: web-standards-glossary-mdn-20260505-0
file: data/developer.mozilla.org/en-US/docs/Glossary/Web_standards-0.md
category: reference
title: Web standards - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/Web_standards
date_saved: 2026-05-05T05:49:23.652432+00:00
instance: kb-cron
parent: web-standards-glossary-mdn-20260505-0
summary:
* [Skip to main content](https://developer.mozilla.org/en-US/docs/Glossary/Web_standards#content) * [Skip to search](https://developer.mozilla.org/en-US/docs/Glossary/Web_standards#search) [ MDN ](https://developer.mozilla.org/en-US/) HTML [HTML: Markup language](https://developer.mozilla.org/en-US/docs/Web/HTML) HTML reference * [Elements](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements) * [Global attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes) * [Attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Attributes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference "See all HTML references") HTML guides * [Responsive images](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Responsive_images) * [HTML cheatsheet](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Cheatsheet) * [Date & time formats](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Date_and_time_formats) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides "See all HTML guides") Markup languages * [SVG](https://developer.mozilla.org/en-US/docs/Web/SVG) * [MathML](https://developer.mozilla.org/en-US/docs/Web/MathML) * [XML](https://developer.mozilla.org/en-US/docs/Web/XML) CSS [CSS: Styling language](https://developer.mozilla.org/en-US/docs/Web/CSS) CSS reference * [Properties](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties) * [Selectors](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors) * [At-rules](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/At-rules) * [Values](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference "See all CSS references") CSS guides * [Box model](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Box_model/Introduction) * [Animations](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Animations/Using) * [Flexbox](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Flexible_box_layout/Basic_concepts) * [Colors](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Colors/Applying_color) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides "See all CSS guides") Layout cookbook * [Column layouts](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Column_layouts) * [Centering an element](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Center_an_element) * [Card component](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Card) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook) JavaScriptJS [JavaScript: Scripting language](https://developer.mozilla.org/en-US/docs/Web/JavaScript) JS reference * [Standard built-in objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects) * [Expressions & operators](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators) * [Statements & declarations](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements) * [Functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference "See all JavaScript references") JS guides * [Control flow & error handing](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Control_flow_and_error_handling) * [Loops and iteration](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration) * [Working with objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_objects) * [Using classes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_classes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide "See all JavaScript guides") Web APIs [Web APIs: Programming interfaces](https://developer.mozilla.org/en-US/docs/Web/API) Web API reference * [File system API](https://developer.mozilla.org/en-US/docs/Web/API/File_System_API) * [Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) * [Geolocation API](https://developer.mozilla.org/en-US/docs/Web/API/Geolocation_API) * [HTML DOM API](https://developer.mozilla.org/en-US/docs/Web/API/HTML_DOM_API) * [Push API](https://developer.mozilla.org/en-US/docs/Web/API/Push_API) * [Service worker API](https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API) * [See all…](https://developer.mozilla.org/en-US/docs/Web/API


id: web-standards-glossary-mdn-20260505-1
file: data/developer.mozilla.org/en-US/docs/Glossary/Web_standards-1.md
category: reference
title: Web standards - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/Web_standards
date_saved: 2026-05-05T05:49:23.652432+00:00
instance: kb-cron
parent: web-standards-glossary-mdn-20260505-0
summary:
## Help improve MDN [Learn how to contribute](https://developer.mozilla.org/en-US/docs/MDN/Community/Getting_started) This page was last modified on Jul 11, 2025 by [MDN contributors](https://developer.mozilla.org/en-US/docs/Glossary/Web_standards/contributors.txt). [View this page on GitHub](https://github.com/mdn/content/blob/main/files/en-us/glossary/web_standards/index.md?plain=1 "Folder: en-us/glossary/web_standards \(Opens in a new tab\)") • [Report a problem with this content](https://github.com/mdn/content/issues/new?template=page-report.yml&mdn-url=https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FWeb_standards&metadata=%3C%21--+Do+not+make+changes+below+this+line+--%3E%0A%3Cdetails%3E%0A%3Csummary%3EPage+report+details%3C%2Fsummary%3E%0A%0A*+Folder%3A+%60en-us%2Fglossary%2Fweb_standards%60%0A*+MDN+URL%3A+https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FWeb_standards%0A*+GitHub+URL%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fblob%2Fmain%2Ffiles%2Fen-us%2Fglossary%2Fweb_standards%2Findex.md%0A*+Last+commit%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fcommit%2F2547f622337d6cbf8c3794776b17ed377d6aad57%0A*+Document+last+modified%3A+2025-07-11T14%3A45%3A59.000Z%0A%0A%3C%2Fdetails%3E "This will take you to GitHub to file a new issue.") 1. [Glossary](https://developer.mozilla.org/en-US/docs/Glossary) 2. 1. [Abstraction](https://developer.mozilla.org/en-US/docs/Glossary/Abstraction) 2. [Accent](https://developer.mozilla.org/en-US/docs/Glossary/Accent) 3. [Accessibility](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility) 4. [Accessibility tree](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility_tree) 5. [Accessible description](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_description) 6. [Accessible name](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_name) 7. [Adobe Flash](https://developer.mozilla.org/en-US/docs/Glossary/Adobe_Flash) 8. [Advance measure](https://developer.mozilla.org/en-US/docs/Glossary/Advance_measure) 9. [Ajax](https://developer.mozilla.org/en-US/docs/Glossary/AJAX) 10. [Algorithm](https://developer.mozilla.org/en-US/docs/Glossary/Algorithm) 11. [Alignment container](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Container) 12. [Alignment subject](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Subject) 13. [Alpha (alpha channel)](https://developer.mozilla.org/en-US/docs/Glossary/Alpha) 14. [ALPN](https://developer.mozilla.org/en-US/docs/Glossary/ALPN) 15. [API](https://developer.mozilla.org/en-US/docs/Glossary/API) 16. [Apple Safari](https://developer.mozilla.org/en-US/docs/Glossary/Apple_Safari) 17. [Application context](https://developer.mozilla.org/en-US/docs/Glossary/Application_context) 18. [Argument](https://developer.mozilla.org/en-US/docs/Glossary/Argument) 19. [ARIA](https://developer.mozilla.org/en-US/docs/Glossary/ARIA) 20. [ARPA](https://developer.mozilla.org/en-US/docs/Glossary/ARPA) 21. [ARPANET](https://developer.mozilla.org/en-US/docs/Glossary/Arpanet) 22. [Array](https://developer.mozilla.org/en-US/docs/Glossary/Array) 23. [ASCII](https://developer.mozilla.org/en-US/docs/Glossary/ASCII) 24. [Aspect ratio](https://developer.mozilla.org/en-US/docs/Glossary/Aspect_ratio) 25. [Asynchronous](https://developer.mozilla.org/en-US/docs/Glossary/Asynchronous) 26. [ATAG](https://developer.mozilla.org/en-US/docs/Glossary/ATAG) 27. [Attribute](https://developer.mozilla.org/en-US/docs/Glossary/Attribute) 28. [Authentication](https://developer.mozilla.org/en-US/docs/Glossary/Authentication) 29. [Authenticator](https://developer.mozilla.org/en-US/docs/Glossary/Authenticator) 30. [Bandwidth](https://developer.mozilla.org/en-US/docs/Glossary/Bandwidth) 31. [Base64](https://developer.mozilla.org/en-US/docs/Glossary/Base64) 32. [Baseline](https://developer.mozilla.org/en-US/docs/Glossary/Baseline) 1. [Baseline (compatibility)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Compatibility) 2. [Baseline (typography)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Typography) 33. [BCP 47 language tag](https://developer.mozilla.org/en-US/docs/Glossary/BCP_47_language_tag) 34. [Beacon](https://developer.mozilla.org/en-US/docs/Glossary/Beacon) 35. [Bézier curve](https://developer.mozilla.org/en-US/docs/Glossary/Bezier_curve) 36. [bfcache](https://developer.mozilla.org/en-US/docs/Glossary/bfcache) 37. [BiDi](https://developer.mozilla.org/en-US/docs/Glossary/BiDi) 38. [BigInt](https://developer.mozilla.org/en-US/docs/Glossary/BigInt) 39. [Binding](https://developer.mozilla.org/en-US/docs/Glossary/Binding) 40. [Bitwise flags](https://developer.mozilla.org/en-US/docs/Glossary/Bitwise_flags) 41. [Blink](https://developer.mozilla.org/en-US/docs/Glossary/Blink) 42. [blink element (<blink> tag)](https://developer.mozilla.org/en-US/docs/Glossary/blink_element) 43. [Block](https://developer.mozilla.org/en-US/docs/Glossary/Block) 1. [Block (CSS)](https://developer.mozilla.org/en-US/docs/Glossary/Block/CSS) 2. [Block (scripting)](https://developer.mozilla.org/en-US/docs/Glossary/Block/Scripting) 44. [Block cipher mode of operation](https://developer.mozilla.org/en-US/docs/Glossary/Block_cipher_mode_of_operation) 45. [Block-level content](https://developer.mozilla.org/en-US/docs/Glossary/Block-level_content) 46. [Boolean](https://developer.mozilla.org/en-US/docs/Glossary/Boolean) 1. [Boolean (JavaScript)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/JavaScript) 2. [Boolean attribute (ARIA)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/ARIA) 3. [Boolean attribute (HTML)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/HTML) 47. [Bounding box](https://developer.mozilla.org/en-US/docs/Glossary/Bounding_box) 48. [Breadcrumb](https://developer.mozilla.org/en-US/docs/Glossary/Breadcrumb) 49. [Brotli


id: whitespace-glossary-mdn-20260505-0
file: data/developer.mozilla.org/en-US/docs/Glossary/Whitespace-0.md
category: reference
title: Whitespace - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/Whitespace
date_saved: 2026-05-05T05:49:26.049959+00:00
instance: kb-cron
parent: whitespace-glossary-mdn-20260505-0
summary:
* [Skip to main content](https://developer.mozilla.org/en-US/docs/Glossary/Whitespace#content) * [Skip to search](https://developer.mozilla.org/en-US/docs/Glossary/Whitespace#search) [ MDN ](https://developer.mozilla.org/en-US/) HTML [HTML: Markup language](https://developer.mozilla.org/en-US/docs/Web/HTML) HTML reference * [Elements](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements) * [Global attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes) * [Attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Attributes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference "See all HTML references") HTML guides * [Responsive images](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Responsive_images) * [HTML cheatsheet](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Cheatsheet) * [Date & time formats](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Date_and_time_formats) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides "See all HTML guides") Markup languages * [SVG](https://developer.mozilla.org/en-US/docs/Web/SVG) * [MathML](https://developer.mozilla.org/en-US/docs/Web/MathML) * [XML](https://developer.mozilla.org/en-US/docs/Web/XML) CSS [CSS: Styling language](https://developer.mozilla.org/en-US/docs/Web/CSS) CSS reference * [Properties](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties) * [Selectors](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors) * [At-rules](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/At-rules) * [Values](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference "See all CSS references") CSS guides * [Box model](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Box_model/Introduction) * [Animations](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Animations/Using) * [Flexbox](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Flexible_box_layout/Basic_concepts) * [Colors](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Colors/Applying_color) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides "See all CSS guides") Layout cookbook * [Column layouts](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Column_layouts) * [Centering an element](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Center_an_element) * [Card component](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Card) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook) JavaScriptJS [JavaScript: Scripting language](https://developer.mozilla.org/en-US/docs/Web/JavaScript) JS reference * [Standard built-in objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects) * [Expressions & operators](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators) * [Statements & declarations](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements) * [Functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference "See all JavaScript references") JS guides * [Control flow & error handing](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Control_flow_and_error_handling) * [Loops and iteration](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration) * [Working with objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_objects) * [Using classes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_classes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide "See all JavaScript guides") Web APIs [Web APIs: Programming interfaces](https://developer.mozilla.org/en-US/docs/Web/API) Web API reference * [File system API](https://developer.mozilla.org/en-US/docs/Web/API/File_System_API) * [Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) * [Geolocation API](https://developer.mozilla.org/en-US/docs/Web/API/Geolocation_API) * [HTML DOM API](https://developer.mozilla.org/en-US/docs/Web/API/HTML_DOM_API) * [Push API](https://developer.mozilla.org/en-US/docs/Web/API/Push_API) * [Service worker API](https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API) * [See all…](https://developer.mozilla.org/en-US/docs/Web/API


id: whitespace-glossary-mdn-20260505-1
file: data/developer.mozilla.org/en-US/docs/Glossary/Whitespace-1.md
category: reference
title: Whitespace - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/Whitespace
date_saved: 2026-05-05T05:49:26.049959+00:00
instance: kb-cron
parent: whitespace-glossary-mdn-20260505-0
summary:
## Help improve MDN [Learn how to contribute](https://developer.mozilla.org/en-US/docs/MDN/Community/Getting_started) This page was last modified on Nov 7, 2025 by [MDN contributors](https://developer.mozilla.org/en-US/docs/Glossary/Whitespace/contributors.txt). [View this page on GitHub](https://github.com/mdn/content/blob/main/files/en-us/glossary/whitespace/index.md?plain=1 "Folder: en-us/glossary/whitespace \(Opens in a new tab\)") • [Report a problem with this content](https://github.com/mdn/content/issues/new?template=page-report.yml&mdn-url=https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FWhitespace&metadata=%3C%21--+Do+not+make+changes+below+this+line+--%3E%0A%3Cdetails%3E%0A%3Csummary%3EPage+report+details%3C%2Fsummary%3E%0A%0A*+Folder%3A+%60en-us%2Fglossary%2Fwhitespace%60%0A*+MDN+URL%3A+https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FWhitespace%0A*+GitHub+URL%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fblob%2Fmain%2Ffiles%2Fen-us%2Fglossary%2Fwhitespace%2Findex.md%0A*+Last+commit%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fcommit%2F85fccefc8066bd49af4ddafc12c77f35265c7e2d%0A*+Document+last+modified%3A+2025-11-07T15%3A58%3A06.000Z%0A%0A%3C%2Fdetails%3E "This will take you to GitHub to file a new issue.") 1. [Glossary](https://developer.mozilla.org/en-US/docs/Glossary) 2. 1. [Abstraction](https://developer.mozilla.org/en-US/docs/Glossary/Abstraction) 2. [Accent](https://developer.mozilla.org/en-US/docs/Glossary/Accent) 3. [Accessibility](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility) 4. [Accessibility tree](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility_tree) 5. [Accessible description](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_description) 6. [Accessible name](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_name) 7. [Adobe Flash](https://developer.mozilla.org/en-US/docs/Glossary/Adobe_Flash) 8. [Advance measure](https://developer.mozilla.org/en-US/docs/Glossary/Advance_measure) 9. [Ajax](https://developer.mozilla.org/en-US/docs/Glossary/AJAX) 10. [Algorithm](https://developer.mozilla.org/en-US/docs/Glossary/Algorithm) 11. [Alignment container](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Container) 12. [Alignment subject](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Subject) 13. [Alpha (alpha channel)](https://developer.mozilla.org/en-US/docs/Glossary/Alpha) 14. [ALPN](https://developer.mozilla.org/en-US/docs/Glossary/ALPN) 15. [API](https://developer.mozilla.org/en-US/docs/Glossary/API) 16. [Apple Safari](https://developer.mozilla.org/en-US/docs/Glossary/Apple_Safari) 17. [Application context](https://developer.mozilla.org/en-US/docs/Glossary/Application_context) 18. [Argument](https://developer.mozilla.org/en-US/docs/Glossary/Argument) 19. [ARIA](https://developer.mozilla.org/en-US/docs/Glossary/ARIA) 20. [ARPA](https://developer.mozilla.org/en-US/docs/Glossary/ARPA) 21. [ARPANET](https://developer.mozilla.org/en-US/docs/Glossary/Arpanet) 22. [Array](https://developer.mozilla.org/en-US/docs/Glossary/Array) 23. [ASCII](https://developer.mozilla.org/en-US/docs/Glossary/ASCII) 24. [Aspect ratio](https://developer.mozilla.org/en-US/docs/Glossary/Aspect_ratio) 25. [Asynchronous](https://developer.mozilla.org/en-US/docs/Glossary/Asynchronous) 26. [ATAG](https://developer.mozilla.org/en-US/docs/Glossary/ATAG) 27. [Attribute](https://developer.mozilla.org/en-US/docs/Glossary/Attribute) 28. [Authentication](https://developer.mozilla.org/en-US/docs/Glossary/Authentication) 29. [Authenticator](https://developer.mozilla.org/en-US/docs/Glossary/Authenticator) 30. [Bandwidth](https://developer.mozilla.org/en-US/docs/Glossary/Bandwidth) 31. [Base64](https://developer.mozilla.org/en-US/docs/Glossary/Base64) 32. [Baseline](https://developer.mozilla.org/en-US/docs/Glossary/Baseline) 1. [Baseline (compatibility)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Compatibility) 2. [Baseline (typography)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Typography) 33. [BCP 47 language tag](https://developer.mozilla.org/en-US/docs/Glossary/BCP_47_language_tag) 34. [Beacon](https://developer.mozilla.org/en-US/docs/Glossary/Beacon) 35. [Bézier curve](https://developer.mozilla.org/en-US/docs/Glossary/Bezier_curve) 36. [bfcache](https://developer.mozilla.org/en-US/docs/Glossary/bfcache) 37. [BiDi](https://developer.mozilla.org/en-US/docs/Glossary/BiDi) 38. [BigInt](https://developer.mozilla.org/en-US/docs/Glossary/BigInt) 39. [Binding](https://developer.mozilla.org/en-US/docs/Glossary/Binding) 40. [Bitwise flags](https://developer.mozilla.org/en-US/docs/Glossary/Bitwise_flags) 41. [Blink](https://developer.mozilla.org/en-US/docs/Glossary/Blink) 42. [blink element (<blink> tag)](https://developer.mozilla.org/en-US/docs/Glossary/blink_element) 43. [Block](https://developer.mozilla.org/en-US/docs/Glossary/Block) 1. [Block (CSS)](https://developer.mozilla.org/en-US/docs/Glossary/Block/CSS) 2. [Block (scripting)](https://developer.mozilla.org/en-US/docs/Glossary/Block/Scripting) 44. [Block cipher mode of operation](https://developer.mozilla.org/en-US/docs/Glossary/Block_cipher_mode_of_operation) 45. [Block-level content](https://developer.mozilla.org/en-US/docs/Glossary/Block-level_content) 46. [Boolean](https://developer.mozilla.org/en-US/docs/Glossary/Boolean) 1. [Boolean (JavaScript)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/JavaScript) 2. [Boolean attribute (ARIA)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/ARIA) 3. [Boolean attribute (HTML)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/HTML) 47. [Bounding box](https://developer.mozilla.org/en-US/docs/Glossary/Bounding_box) 48. [Breadcrumb](https://developer.mozilla.org/en-US/docs/Glossary/Breadcrumb) 49. [Brotli


id: windowproxy-glossary-mdn-20260505-0
file: data/developer.mozilla.org/en-US/docs/Glossary/WindowProxy-0.md
category: reference
title: WindowProxy - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/WindowProxy
date_saved: 2026-05-05T05:49:28.328809+00:00
instance: kb-cron
parent: windowproxy-glossary-mdn-20260505-0
summary:
* [Skip to main content](https://developer.mozilla.org/en-US/docs/Glossary/WindowProxy#content) * [Skip to search](https://developer.mozilla.org/en-US/docs/Glossary/WindowProxy#search) [ MDN ](https://developer.mozilla.org/en-US/) HTML [HTML: Markup language](https://developer.mozilla.org/en-US/docs/Web/HTML) HTML reference * [Elements](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Elements) * [Global attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Global_attributes) * [Attributes](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference/Attributes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Reference "See all HTML references") HTML guides * [Responsive images](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Responsive_images) * [HTML cheatsheet](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Cheatsheet) * [Date & time formats](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides/Date_and_time_formats) * [See all…](https://developer.mozilla.org/en-US/docs/Web/HTML/Guides "See all HTML guides") Markup languages * [SVG](https://developer.mozilla.org/en-US/docs/Web/SVG) * [MathML](https://developer.mozilla.org/en-US/docs/Web/MathML) * [XML](https://developer.mozilla.org/en-US/docs/Web/XML) CSS [CSS: Styling language](https://developer.mozilla.org/en-US/docs/Web/CSS) CSS reference * [Properties](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Properties) * [Selectors](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Selectors) * [At-rules](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/At-rules) * [Values](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference/Values) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Reference "See all CSS references") CSS guides * [Box model](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Box_model/Introduction) * [Animations](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Animations/Using) * [Flexbox](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Flexible_box_layout/Basic_concepts) * [Colors](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Colors/Applying_color) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides "See all CSS guides") Layout cookbook * [Column layouts](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Column_layouts) * [Centering an element](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Center_an_element) * [Card component](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook/Card) * [See all…](https://developer.mozilla.org/en-US/docs/Web/CSS/How_to/Layout_cookbook) JavaScriptJS [JavaScript: Scripting language](https://developer.mozilla.org/en-US/docs/Web/JavaScript) JS reference * [Standard built-in objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects) * [Expressions & operators](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators) * [Statements & declarations](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements) * [Functions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference "See all JavaScript references") JS guides * [Control flow & error handing](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Control_flow_and_error_handling) * [Loops and iteration](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration) * [Working with objects](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_objects) * [Using classes](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_classes) * [See all…](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide "See all JavaScript guides") Web APIs [Web APIs: Programming interfaces](https://developer.mozilla.org/en-US/docs/Web/API) Web API reference * [File system API](https://developer.mozilla.org/en-US/docs/Web/API/File_System_API) * [Fetch API](https://developer.mozilla.org/en-US/docs/Web/API/Fetch_API) * [Geolocation API](https://developer.mozilla.org/en-US/docs/Web/API/Geolocation_API) * [HTML DOM API](https://developer.mozilla.org/en-US/docs/Web/API/HTML_DOM_API) * [Push API](https://developer.mozilla.org/en-US/docs/Web/API/Push_API) * [Service worker API](https://developer.mozilla.org/en-US/docs/Web/API/Service_Worker_API) * [See all…](https://developer.mozilla.org/en-US/docs/Web/API


id: windowproxy-glossary-mdn-20260505-1
file: data/developer.mozilla.org/en-US/docs/Glossary/WindowProxy-1.md
category: reference
title: WindowProxy - Glossary | MDN
tags: web, html, css, javascript, documentation
source_url: https://developer.mozilla.org/en-US/docs/Glossary/WindowProxy
date_saved: 2026-05-05T05:49:28.328809+00:00
instance: kb-cron
parent: windowproxy-glossary-mdn-20260505-0
summary:
## Help improve MDN [Learn how to contribute](https://developer.mozilla.org/en-US/docs/MDN/Community/Getting_started) This page was last modified on Jul 11, 2025 by [MDN contributors](https://developer.mozilla.org/en-US/docs/Glossary/WindowProxy/contributors.txt). [View this page on GitHub](https://github.com/mdn/content/blob/main/files/en-us/glossary/windowproxy/index.md?plain=1 "Folder: en-us/glossary/windowproxy \(Opens in a new tab\)") • [Report a problem with this content](https://github.com/mdn/content/issues/new?template=page-report.yml&mdn-url=https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FWindowProxy&metadata=%3C%21--+Do+not+make+changes+below+this+line+--%3E%0A%3Cdetails%3E%0A%3Csummary%3EPage+report+details%3C%2Fsummary%3E%0A%0A*+Folder%3A+%60en-us%2Fglossary%2Fwindowproxy%60%0A*+MDN+URL%3A+https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FGlossary%2FWindowProxy%0A*+GitHub+URL%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fblob%2Fmain%2Ffiles%2Fen-us%2Fglossary%2Fwindowproxy%2Findex.md%0A*+Last+commit%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fcommit%2F2547f622337d6cbf8c3794776b17ed377d6aad57%0A*+Document+last+modified%3A+2025-07-11T14%3A45%3A59.000Z%0A%0A%3C%2Fdetails%3E "This will take you to GitHub to file a new issue.") 1. [Glossary](https://developer.mozilla.org/en-US/docs/Glossary) 2. 1. [Abstraction](https://developer.mozilla.org/en-US/docs/Glossary/Abstraction) 2. [Accent](https://developer.mozilla.org/en-US/docs/Glossary/Accent) 3. [Accessibility](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility) 4. [Accessibility tree](https://developer.mozilla.org/en-US/docs/Glossary/Accessibility_tree) 5. [Accessible description](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_description) 6. [Accessible name](https://developer.mozilla.org/en-US/docs/Glossary/Accessible_name) 7. [Adobe Flash](https://developer.mozilla.org/en-US/docs/Glossary/Adobe_Flash) 8. [Advance measure](https://developer.mozilla.org/en-US/docs/Glossary/Advance_measure) 9. [Ajax](https://developer.mozilla.org/en-US/docs/Glossary/AJAX) 10. [Algorithm](https://developer.mozilla.org/en-US/docs/Glossary/Algorithm) 11. [Alignment container](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Container) 12. [Alignment subject](https://developer.mozilla.org/en-US/docs/Glossary/Alignment_Subject) 13. [Alpha (alpha channel)](https://developer.mozilla.org/en-US/docs/Glossary/Alpha) 14. [ALPN](https://developer.mozilla.org/en-US/docs/Glossary/ALPN) 15. [API](https://developer.mozilla.org/en-US/docs/Glossary/API) 16. [Apple Safari](https://developer.mozilla.org/en-US/docs/Glossary/Apple_Safari) 17. [Application context](https://developer.mozilla.org/en-US/docs/Glossary/Application_context) 18. [Argument](https://developer.mozilla.org/en-US/docs/Glossary/Argument) 19. [ARIA](https://developer.mozilla.org/en-US/docs/Glossary/ARIA) 20. [ARPA](https://developer.mozilla.org/en-US/docs/Glossary/ARPA) 21. [ARPANET](https://developer.mozilla.org/en-US/docs/Glossary/Arpanet) 22. [Array](https://developer.mozilla.org/en-US/docs/Glossary/Array) 23. [ASCII](https://developer.mozilla.org/en-US/docs/Glossary/ASCII) 24. [Aspect ratio](https://developer.mozilla.org/en-US/docs/Glossary/Aspect_ratio) 25. [Asynchronous](https://developer.mozilla.org/en-US/docs/Glossary/Asynchronous) 26. [ATAG](https://developer.mozilla.org/en-US/docs/Glossary/ATAG) 27. [Attribute](https://developer.mozilla.org/en-US/docs/Glossary/Attribute) 28. [Authentication](https://developer.mozilla.org/en-US/docs/Glossary/Authentication) 29. [Authenticator](https://developer.mozilla.org/en-US/docs/Glossary/Authenticator) 30. [Bandwidth](https://developer.mozilla.org/en-US/docs/Glossary/Bandwidth) 31. [Base64](https://developer.mozilla.org/en-US/docs/Glossary/Base64) 32. [Baseline](https://developer.mozilla.org/en-US/docs/Glossary/Baseline) 1. [Baseline (compatibility)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Compatibility) 2. [Baseline (typography)](https://developer.mozilla.org/en-US/docs/Glossary/Baseline/Typography) 33. [BCP 47 language tag](https://developer.mozilla.org/en-US/docs/Glossary/BCP_47_language_tag) 34. [Beacon](https://developer.mozilla.org/en-US/docs/Glossary/Beacon) 35. [Bézier curve](https://developer.mozilla.org/en-US/docs/Glossary/Bezier_curve) 36. [bfcache](https://developer.mozilla.org/en-US/docs/Glossary/bfcache) 37. [BiDi](https://developer.mozilla.org/en-US/docs/Glossary/BiDi) 38. [BigInt](https://developer.mozilla.org/en-US/docs/Glossary/BigInt) 39. [Binding](https://developer.mozilla.org/en-US/docs/Glossary/Binding) 40. [Bitwise flags](https://developer.mozilla.org/en-US/docs/Glossary/Bitwise_flags) 41. [Blink](https://developer.mozilla.org/en-US/docs/Glossary/Blink) 42. [blink element (<blink> tag)](https://developer.mozilla.org/en-US/docs/Glossary/blink_element) 43. [Block](https://developer.mozilla.org/en-US/docs/Glossary/Block) 1. [Block (CSS)](https://developer.mozilla.org/en-US/docs/Glossary/Block/CSS) 2. [Block (scripting)](https://developer.mozilla.org/en-US/docs/Glossary/Block/Scripting) 44. [Block cipher mode of operation](https://developer.mozilla.org/en-US/docs/Glossary/Block_cipher_mode_of_operation) 45. [Block-level content](https://developer.mozilla.org/en-US/docs/Glossary/Block-level_content) 46. [Boolean](https://developer.mozilla.org/en-US/docs/Glossary/Boolean) 1. [Boolean (JavaScript)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/JavaScript) 2. [Boolean attribute (ARIA)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/ARIA) 3. [Boolean attribute (HTML)](https://developer.mozilla.org/en-US/docs/Glossary/Boolean/HTML) 47. [Bounding box](https://developer.mozilla.org/en-US/docs/Glossary/Bounding_box) 48. [Breadcrumb](https://developer.mozilla.org/en-US/docs/Glossary/Breadcrumb) 49. [Brotli


