---
title: "Changelog - Learn web development | MDN"
chunk: 2/3
source: "https://developer.mozilla.org/en-US/docs/Learn_web_development/Changelog"
category: "reference"
tags: "web, html, css, javascript, documentation"
date_saved: "2026-05-05T05:50:18.262377+00:00"
instance: "kb-cron"
---

The [original curriculum pages](https://developer.mozilla.org/en-US/curriculum/) are being kept as a summary of the Learn web development content that is useful for educators when planning curricula.
Moving forward, we will continue to update the content and design to make Learn web development even more useful to learners and educators.
##  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 21, 2025 by [MDN contributors](https://developer.mozilla.org/en-US/docs/Learn_web_development/Changelog/contributors.txt). 
[View this page on GitHub](https://github.com/mdn/content/blob/main/files/en-us/learn_web_development/changelog/index.md?plain=1 "Folder: en-us/learn_web_development/changelog \(Opens in a new tab\)") • [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%2FLearn_web_development%2FChangelog&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%2Flearn_web_development%2Fchangelog%60%0A*+MDN+URL%3A+https%3A%2F%2Fdeveloper.mozilla.org%2Fen-US%2Fdocs%2FLearn_web_development%2FChangelog%0A*+GitHub+URL%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fblob%2Fmain%2Ffiles%2Fen-us%2Flearn_web_development%2Fchangelog%2Findex.md%0A*+Last+commit%3A+https%3A%2F%2Fgithub.com%2Fmdn%2Fcontent%2Fcommit%2F02eafb53ee0b481bc4a60e7da630811201fe228a%0A*+Document+last+modified%3A+2025-08-21T12%3A21%3A45.000Z%0A%0A%3C%2Fdetails%3E "This will take you to GitHub to file a new issue.")
  1. [Learn web development](https://developer.mozilla.org/en-US/docs/Learn_web_development)
  2. [MDN curriculum](https://developer.mozilla.org/en-US/curriculum/)
  3. [Getting started modules](https://developer.mozilla.org/en-US/docs/Learn_web_development/Getting_started)
  4. [Environment setup](https://developer.mozilla.org/en-US/docs/Learn_web_development/Getting_started/Environment_setup)
    1. [Installing software](https://developer.mozilla.org/en-US/docs/Learn_web_development/Getting_started/Environment_setup/Installing_software)
    2. [Browsing the web](https://developer.mozilla.org/en-US/docs/Learn_web_development/Getting_started/Environment_setup/Browsing_the_web)
    3. [Code editors](https://developer.mozilla.org/en-US/docs/Learn_web_development/Getting_started/Environment_setup/Code_editors)
    4. [Dealing with files](https://developer.mozilla.org/en-US/docs/Learn_web_development/Getting_started/Environment_setup/Dealing_with_files)
    5. [Command line](https://developer.mozilla.org/en-US/docs/Learn_web_development/Getting_started/Environment_setup/Command_line)
  5. [Your first website](https://developer.mozilla.org/en-US/docs/Learn_web_development/Getting_started/Your_first_website)
    1. [What will it look like?](https://developer.mozilla.org/en-US/docs/Learn_web_development/Getting_started/Your_first_website/What_will_your_website_look_like)
    2. [Creating the content](https://developer.mozilla.org/en-US/docs/Learn_web_development/Getting_started/Your_first_website/Creating_the_content)
    3. [Styling the content](https://developer.mozilla.org/en-US/docs/Learn_web_development/Getting_started/Your_first_website/Styling_the_content)
    4. [Adding interactivity](https://developer.mozilla.org/en-US/docs/Learn_web_development/Getting_started/Your_first_website/Adding_interactivity)
    5. [Publishing](https://developer.mozilla.org/en-US/docs/Learn_web_development/Getting_started/Your_first_website/Publishing_your_website)
  6. [Web standards](https://developer.mozilla.org/en-US/docs/Learn_web_development/Getting_started/Web_standards)
    1. [How the web works](https://developer.mozilla.org/en-US/docs/Learn_web_development/Getting_started/Web_standards/How_the_web_works)
    2. [The web standards model](https://developer.mozilla.org/en-US/docs/Learn_web_development/Getting_started/Web_standards/The_web_standards_model)
    3. [How browsers load websites](https://developer.mozilla.org/en-US/docs/Learn_web_development/Getting_started/Web_standards/How_browsers_load_websites)
  7. [Soft skills](https://developer.mozilla.org/en-US/docs/Learn_web_development/Getting_started/Soft_skills)
    1. [Research and learning](https://developer.mozilla.org/en-US/docs/Learn_web_development/Getting_started/Soft_skills/Research_and_learning)
    2. [Collaboration and teamwork](https://developer.mozilla.org/en-US/docs/Learn_web_development/Getting_started/Soft_skills/Collaboration_and_teamwork)
    3. [Workflows and processes](https://developer.mozilla.org/en-US/docs/Learn_web_development/Getting_started/Soft_skills/Workflows_and_processes)
    4. [Finding a job](https://developer.mozilla.org/en-US/docs/Learn_web_development/Getting_started/Soft_skills/Finding_a_job)
  8. [Core modules](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core)
  9. [Structuring content with HTML](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Structuring_content)
    1. [Basic HTML syntax](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Structuring_content/Basic_HTML_syntax)
    2. [Web page metadata](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Structuring_content/Webpage_metadata)
    3. [Headings and paragraphs](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Structuring_content/Headings_and_paragraphs)
    4. [Emphasis and importance](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Structuring_content/Emphasis_and_importance)
    5. [Lists](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Structuring_content/Lists)
    6. [Test: HTML text basics](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Structuring_content/Test_your_skills/HTML_text_basics)
    7. [Advanced text features](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Structuring_content/Advanced_text_features)
    8. [Test: Advanced HTML text](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Structuring_content/Test_your_skills/Advanced_HTML_text)
    9. [Challenge: Letter markup](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Structuring_content/Marking_up_a_letter)
    10. [Structuring documents](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Structuring_content/Structuring_documents)
    11. [Creating links](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Structuring_content/Creating_links)
    12. [Test: Links](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Structuring_content/Test_your_skills/Links)
    13. [Challenge: Bird watching site](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Structuring_content/Structuring_a_page_of_content)
    14. [Images](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Structuring_content/HTML_images)
    15. [Test: Images](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Structuring_content/Test_your_skills/Images)
    16. [Video and audio](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Structuring_content/HTML_video_and_audio)
    17. [Test: Audio and video](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Structuring_content/Test_your_skills/Audio_and_video)
    18. [Challenge: Splash page](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Structuring_content/Splash_page)
    19. [Table basics](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Structuring_content/HTML_table_basics)
    20. [Table accessibility](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Structuring_content/Table_accessibility)
    21. [Challenge: Planet data table](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Structuring_content/Planet_data_table)
    22. [Forms and buttons](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Structuring_content/HTML_forms)
    23. [Test: Forms and buttons](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Structuring_content/Test_your_skills/Forms_and_buttons)
    24. [Challenge: Feedback form](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Structuring_content/Forms_challenge)
    25. [Debugging HTML](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Structuring_content/Debugging_HTML)
    26. [Test: HTML tests index](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Structuring_content/Test_your_skills)
    27. Additional tutorials
      1. [Vector graphics](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Structuring_content/Including_vector_graphics_in_HTML)
      2. [Embedding technologies](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Structuring_content/General_embedding_technologies)
  10. [CSS styling basics](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Styling_basics)
    1. [What is CSS?](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Styling_basics/What_is_CSS)
    2. [CSS getting started](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Styling_basics/Getting_started)
    3. [Challenge: Biography page](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Styling_basics/Styling_a_bio_page)
    4. [Basic selectors](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Styling_basics/Basic_selectors)
    5. [Attribute selectors](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Styling_basics/Attribute_selectors)
    6. [Pseudo-classes and elements](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Styling_basics/Pseudo_classes_and_elements)
    7. [Combinators](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Styling_basics/Combinators)
    8. [Test: Selectors](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Styling_basics/Test_your_skills/Selectors)
    9. [Box model](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Styling_basics/Box_model)
    10. [Test: Box model](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Styling_basics/Test_your_skills/Box_model)
    11. [Handling conflicts](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Styling_basics/Handling_conflicts)
    12. [Test: Cascade](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Styling_basics/Test_your_skills/Cascade)
    13. [Challenge: Fixing blog styles](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Styling_basics/Fixing_blog_styles)
    14. [Values and units](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Styling_basics/Values_and_units)
    15. [Test: Values and units](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Styling_basics/Test_your_skills/Values)
    16. [Sizing](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Styling_basics/Sizing)
    17. [Test: Sizing](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Styling_basics/Test_your_skills/Sizing)
    18. [Backgrounds and borders](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Styling_basics/Backgrounds_and_borders)
    19. [Test: Backgrounds and borders](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Styling_basics/Test_your_skills/Backgrounds_and_borders)
    20. [Overflow](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Styling_basics/Overflow)
    21. [Test: Overflow](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Styling_basics/Test_your_skills/Overflow)
    22. [Challenge: Sizing and decorating](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Styling_basics/Size_decorate_content_panel)
    23. [Images, media, forms](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Styling_basics/Images_media_forms)
    24. [Test: Images and forms](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Styling_basics/Test_your_skills/Images)
    25. [Styling tables](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Styling_basics/Tables)
    26. [Challenge: Styling color scheme search](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Styling_basics/Home_color_scheme_search)
    27. [Debugging CSS](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Styling_basics/Debugging_CSS)
    28. [Test: Styling basics tests index](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Styling_basics/Test_your_skills)
    29. Additional tutorials
      1. [Advanced styling effects](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Styling_basics/Advanced_styling_effects)
      2. [Cascade layers](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Styling_basics/Cascade_layers)
      3. [Multiple text directions](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Styling_basics/Handling_different_text_directions)
      4. [Organizing your CSS](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Styling_basics/Organizing)
  11. [CSS text styling](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Text_styling)
    1. [Text and font fundamentals](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Text_styling/Fundamentals)
    2. [Styling lists](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Text_styling/Styling_lists)
    3. [Styling links](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Text_styling/Styling_links)
    4. [Web fonts](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Text_styling/Web_fonts)
    5. [Challenge: Community school homepage](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Text_styling/Typesetting_a_homepage)
  12. [CSS layout](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/CSS_layout)
    1. [Introduction](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/CSS_layout/Introduction)
    2. [Floats](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/CSS_layout/Floats)
    3. [Test: Floats](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/CSS_layout/Test_your_skills/Floats)
    4. [Positioning](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/CSS_layout/Positioning)
    5. [Test: Positioning](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/CSS_layout/Test_your_skills/Position)
    6. [Flexbox](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/CSS_layout/Flexbox)
    7. [Test: Flexbox](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/CSS_layout/Test_your_skills/Flexbox)
    8. [CSS grid layout](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/CSS_layout/Grids)
    9. [Test: CSS grid](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/CSS_layout/Test_your_skills/Grid)
    10. [Challenge: Fundamental layout](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/CSS_layout/Fundamental_Layout_Comprehension)
    11. [Responsive web design](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/CSS_layout/Responsive_Design)
    12. [Media queries](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/CSS_layout/Media_queries)
    13. [Test: RWD & media queries](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/CSS_layout/Test_your_skills/Responsive_design)
    14. [Challenge: mobile-first](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/CSS_layout/Mobile-first_challenge)
    15. [Test: Layout tests index](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/CSS_layout/Test_your_skills)
    16. Additional tutorials
      1. [Multiple-column layout](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/CSS_layout/Multiple-column_Layout)
      2. [Practical positioning examples](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/CSS_layout/Practical_positioning_examples)
      3. [Legacy layout methods](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/CSS_layout/Legacy_Layout_Methods)
      4. [Supporting older browsers](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/CSS_layout/Supporting_Older_Browsers)
  13. [Dynamic scripting with JavaScript](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Scripting)
    1. [What is JavaScript?](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Scripting/What_is_JavaScript)
    2. [JavaScript walkthrough](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Scripting/A_first_splash)
    3. [Troubleshooting](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Scripting/What_went_wrong)
    4. [Variables](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Scripting/Variables)
    5. [Test: Variables](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Scripting/Test_your_skills/Variables)
    6. [Numbers and operators](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Scripting/Math)
    7. [Test: Math](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Scripting/Test_your_skills/Math)
    8. [Strings](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Scripting/Strings)
    9. [String methods](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Scripting/Useful_string_methods)
    10. [Test: Strings](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Scripting/Test_your_skills/Strings)
    11. [Arrays](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Scripting/Arrays)
    12. [Test: Arrays](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Scripting/Test_your_skills/Arrays)
    13. [Challenge: Story generator](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Scripting/Silly_story_generator)
    14. [Conditionals](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Scripting/Conditionals)
    15. [Test: Conditionals](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Scripting/Test_your_skills/Conditionals)
    16. [Loops](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Scripting/Loops)
    17. [Test: Loops](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Scripting/Test_your_skills/Loops)
    18. [Functions](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Scripting/Functions)
    19. [Build your own function](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Scripting/Build_your_own_function)
    20. [Function return values](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Scripting/Return_values)
    21. [Test: Functions](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Scripting/Test_your_skills/Functions)
    22. [Events](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Scripting/Events)
    23. [Event bubbling](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Scripting/Event_bubbling)
    24. [Test: Events](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Scripting/Test_your_skills/Events)
    25. [Objects](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Scripting/Object_basics)
    26. [Test: Objects](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Scripting/Test_your_skills/Object_basics)
    27. [DOM scripting](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Scripting/DOM_scripting)
    28. [Challenge: Image gallery](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Scripting/Image_gallery)
    29. [Network requests](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Scripting/Network_requests)
    30. [JSON](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Scripting/JSON)
    31. [Test: JSON](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Scripting/Test_your_skills/JSON)
    32. [Challenge: House data UI](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Scripting/House_data_UI)
    33. [Debugging and error handling](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Scripting/Debugging_JavaScript)
    34. [Test: JavaScript tests index](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Scripting/Test_your_skills)
  14. [JavaScript frameworks and libraries](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Frameworks_libraries)
    1. [Introduction](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Frameworks_libraries/Introduction)
    2. [Framework features](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Frameworks_libraries/Main_features)
    3. [React getting started](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Frameworks_libraries/React_getting_started)
    4. [React ToDo app](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Frameworks_libraries/React_todo_list_beginning)
    5. [React components](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Frameworks_libraries/React_components)
    6. [React events and state](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Frameworks_libraries/React_interactivity_events_state)
    7. [React editing, filtering, conditional UI](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Frameworks_libraries/React_interactivity_filtering_conditional_rendering)
    8. [React accessibility](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Frameworks_libraries/React_accessibility)
    9. [React resources](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Frameworks_libraries/React_resources)
  15. [Accessibility](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Accessibility)
    1. [What is accessibility?](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Accessibility/What_is_accessibility)
    2. [Accessibility tools](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Accessibility/Tooling)
    3. [Accessible HTML](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Accessibility/HTML)
    4. [Test: HTML a11y](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Accessibility/Test_your_skills/HTML)
    5. [Accessible CSS and JS](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Accessibility/CSS_and_JavaScript)
    6. [Test: CSS/JS a11y](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Accessibility/Test_your_skills/CSS_and_JavaScript)
    7. [WAI-ARIA](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Accessibility/WAI-ARIA_basics)
    8. [Test: WAI-ARIA](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Accessibility/Test_your_skills/WAI-ARIA)
    9. [Accessible multimedia](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Accessibility/Multimedia)
    10. [Mobile accessibility](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Accessibility/Mobile)
    11. [Challenge: A11y debugging](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Accessibility/Accessibility_troubleshooting)
    12. [Test: A11y tests index](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Accessibility/Test_your_skills)
  16. [Design for developers](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Design_for_developers)
  17. [Version control](https://developer.mozilla.org/en-US/docs/Learn_web_development/Core/Version_control)
  18. [Extension modules](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions)
  19. [Advanced JavaScript objects](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects)
    1. [Object prototypes](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Object_prototypes)
    2. [Object-oriented programming](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Object-oriented_programming)
    3. [Classes in JavaScript](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Classes_in_JavaScript)
    4. [Test: Object-oriented JavaScript](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Test_your_skills/Object-oriented_JavaScript)
    5. [Object building practice](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Object_building_practice)
    6. [Challenge: Bouncing balls features](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Adding_bouncing_balls_features)
    7. [Test: OOJS tests index](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Advanced_JavaScript_objects/Test_your_skills)
  20. [Client-side web APIs](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Client-side_APIs)
    1. [Introduction](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Client-side_APIs/Introduction)
    2. [Video and audio](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Client-side_APIs/Video_and_audio_APIs)
    3. [Drawing graphics](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Client-side_APIs/Drawing_graphics)
    4. [Client-side storage](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Client-side_APIs/Client-side_storage)
    5. [Third-party APIs](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Client-side_APIs/Third_party_APIs)
  21. [Asynchronous JavaScript](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Async_JS)
    1. [Introduction](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Async_JS/Introducing)
    2. [Using promises](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Async_JS/Promises)
    3. [Implementing promise-based APIs](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Async_JS/Implementing_a_promise-based_API)
    4. [Introducing workers](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Async_JS/Introducing_workers)
    5. [Challenge: Animation sequence](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Async_JS/Sequencing_animations)
  22. [Web forms](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Forms)
    1. [Your first form](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Forms/Your_first_form)
    2. [How to structure a web form](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Forms/How_to_structure_a_web_form)
    3. [Basic native form controls](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Forms/Basic_native_form_controls)
    4. [The HTML5 input types](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Forms/HTML5_input_types)
    5. [Other form controls](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Forms/Other_form_controls)
    6. [Styling web forms](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Forms/Styling_web_forms)
    7. [Advanced form styling](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Forms/Advanced_form_styling)
    8. [Customizable selects](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Forms/Customizable_select)
    9. [Customizable listboxes](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Forms/Customizable_select_listboxes)
    10. [UI pseudo-classes](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Forms/UI_pseudo-classes)
    11. [Client-side form validation](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Forms/Form_validation)
    12. [Sending form data](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Forms/Sending_and_retrieving_form_data)
    13. Additional tutorials
      1. [Custom form controls](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Forms/How_to_build_custom_form_controls)
      2. [JS form submission](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Forms/Sending_forms_through_JavaScript)
      3. [Forms in legacy browsers](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Forms/HTML_forms_in_legacy_browsers)
      4. [UI methods & controls](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Forms/User_input_methods)
  23. [Understanding client-side tools](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Client-side_tools)
    1. [Overview](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Client-side_tools/Overview)
    2. [Package management](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Client-side_tools/Package_management)
    3. [Sample toolchain](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Client-side_tools/Introducing_complete_toolchain)
    4. [Deploying our app](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Client-side_tools/Deployment)
  24. [Server-side websites](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Server-side)
    1. [First steps](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Server-side/First_steps)
      1. [Introduction](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Server-side/First_steps/Introduction)
      2. [Client-server overview](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Server-side/First_steps/Client-Server_overview)
      3. [Server-side frameworks](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Server-side/First_steps/Web_frameworks)
      4. [Website security](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Server-side/First_steps/Website_security)
    2. [Django (Python)](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Server-side/Django)
      1. [Django introduction](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Server-side/Django/Introduction)
      2. [Dev environment setup](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Server-side/Django/development_environment)
      3. [1: Local library tutorial](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Server-side/Django/Tutorial_local_library_website)
      4. [2: Skeleton website](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Server-side/Django/skeleton_website)
      5. [3: Models](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Server-side/Django/Models)
      6. [4: Django admin site](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Server-side/Django/Admin_site)
      7. [5: Home page](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Server-side/Django/Home_page)
      8. [6: Generic list and detail views](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Server-side/Django/Generic_views)
      9. [7: Sessions framework](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Server-side/Django/Sessions)
      10. [8: Authentication and permissions](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Server-side/Django/Authentication)
      11. [9: Forms](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Server-side/Django/Forms)
      12. [10: Testing](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Server-side/Django/Testing)
      13. [11: Deploying](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Server-side/Django/Deployment)
      14. [Django security](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Server-side/Django/web_application_security)
      15. [Challenge: Django blog](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Server-side/Django/django_assessment_blog)
    3. [Express (Node.js)](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs)
      1. [Express/Node introduction](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/Introduction)
      2. [Dev environment setup](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/development_environment)
      3. [1: Local library tutorial](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/Tutorial_local_library_website)
      4. [2: Skeleton website](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/skeleton_website)
      5. [3: Using databases with Mongoose](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/mongoose)
      6. [4: Routes and controllers](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/routes)
      7. [5: Displaying data](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/Displaying_data)
      8. [6: Working with forms](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/forms)
      9. [7: Deploying](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Server-side/Express_Nodejs/deployment)
    4. Additional tutorials
      1. [Apache .htaccess](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Server-side/Apache_Configuration_htaccess)
      2. [Server MIME type config](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Server-side/Configuring_server_MIME_types)
      3. [Plain Node.js server](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Server-side/Node_server_without_framework)
  25. [Web performance](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Performance)
    1. [The "why" of web performance](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Performance/why_web_performance)
    2. [What is web performance?](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Performance/What_is_web_performance)
    3. [Perceived performance](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Performance/Perceived_performance)
    4. [Measuring performance](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Performance/Measuring_performance)
    5. [Multimedia: Images](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Performance/Multimedia)
    6. [Multimedia: video](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Performance/video)
    7. [Performant JavaScript](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Performance/JavaScript)
    8. [Performant HTML](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Performance/HTML)
    9. [Performant CSS](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Performance/CSS)
    10. [Performance business case](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Performance/business_case_for_performance)
    11. [Best practices & tips](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Performance/Best_practices)
  26. [Testing](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Testing)
    1. [Introduction](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Testing/Introduction)
    2. [Testing strategies](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Testing/Testing_strategies)
    3. [Common HTML and CSS problems](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Testing/HTML_and_CSS)
    4. [Feature detection](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Testing/Feature_detection)
    5. [Automated testing](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Testing/Automated_testing)
    6. [Automation environment setup](https://developer.mozilla.org/en-US/docs/Learn_web_development/Extensions/Testing/Your_own_automation_environment)
  27. Further resources
  28. [How to solve common problems](https://developer.mozilla.org/en-US/docs/Learn_web_development/Howto)
    1. [Common CSS problems](https://developer.mozilla.org/en-US/docs/Learn_web_development/Howto/Solve_CSS_problems)
    2. [Common HTML problems](https://developer.mozilla.org/en-US/docs/Learn_web_development/Howto/Solve_HTML_problems)
    3. [Common JavaScript problems](https://developer.mozilla.org/en-US/docs/Learn_web_development/Howto/Solve_JavaScript_problems)
    4. [Design and accessibility](https://developer.mozilla.org/en-US/docs/Learn_web_development/Howto/Design_and_accessibility)
    5. [Tools and setup](https://developer.mozilla.org/en-US/docs/Learn_web_development/Howto/Tools_and_setup)
    6. [Web mechanics](https://developer.mozilla.org/en-US/docs/Learn_web_development/Howto/Web_mechanics)
  29. [About](https://developer.mozilla.org/en-US/docs/Learn_web_development/About)
  30. [Resources for educators](https://developer.mozilla.org/en-US/docs/Learn_web_development/Educators)
  31. _[Changelog](https://developer.mozilla.org/en-US/docs/Learn_web_development/Changelog)_