---
title: "CSS - Glossary | MDN"
chunk: 3/3
source: "https://developer.mozilla.org/en-US/docs/Glossary/CSS"
category: "reference"
tags: "web, html, css, javascript, documentation"
date_saved: "2026-05-05T05:26:26.538347+00:00"
instance: "kb-cron"
---

[Relying party](https://developer.mozilla.org/en-US/docs/Glossary/Relying_party)
    421. [Render-blocking](https://developer.mozilla.org/en-US/docs/Glossary/Render_blocking)
    422. [Repaint](https://developer.mozilla.org/en-US/docs/Glossary/Repaint)
    423. [Replaced elements](https://developer.mozilla.org/en-US/docs/Glossary/Replaced_elements)
    424. [Replay attack](https://developer.mozilla.org/en-US/docs/Glossary/Replay_attack)
    425. [Repo](https://developer.mozilla.org/en-US/docs/Glossary/Repo)
    426. [Reporting directive](https://developer.mozilla.org/en-US/docs/Glossary/Reporting_directive)
    427. [Representation header](https://developer.mozilla.org/en-US/docs/Glossary/Representation_header)
    428. [Request header](https://developer.mozilla.org/en-US/docs/Glossary/Request_header)
    429. [Resource Timing](https://developer.mozilla.org/en-US/docs/Glossary/Resource_Timing)
    430. [Response header](https://developer.mozilla.org/en-US/docs/Glossary/Response_header)
    431. [Responsive Web Design (RWD)](https://developer.mozilla.org/en-US/docs/Glossary/Responsive_web_design)
    432. [REST](https://developer.mozilla.org/en-US/docs/Glossary/REST)
    433. [RGB](https://developer.mozilla.org/en-US/docs/Glossary/RGB)
    434. [RIL](https://developer.mozilla.org/en-US/docs/Glossary/RIL)
    435. [Robots.txt](https://developer.mozilla.org/en-US/docs/Glossary/Robots.txt)
    436. [Round Trip Time (RTT)](https://developer.mozilla.org/en-US/docs/Glossary/Round_Trip_Time)
    437. [Router](https://developer.mozilla.org/en-US/docs/Glossary/Router)
    438. [RSS](https://developer.mozilla.org/en-US/docs/Glossary/RSS)
    439. [Rsync](https://developer.mozilla.org/en-US/docs/Glossary/Rsync)
    440. [RTCP (RTP Control Protocol)](https://developer.mozilla.org/en-US/docs/Glossary/RTCP)
    441. [RTF](https://developer.mozilla.org/en-US/docs/Glossary/RTF)
    442. [RTL (Right to Left)](https://developer.mozilla.org/en-US/docs/Glossary/RTL)
    443. [RTP (Real-time Transport Protocol) and SRTP (Secure RTP)](https://developer.mozilla.org/en-US/docs/Glossary/RTP)
    444. [RTSP: Real-time streaming protocol](https://developer.mozilla.org/en-US/docs/Glossary/RTSP)
    445. [Ruby](https://developer.mozilla.org/en-US/docs/Glossary/Ruby)
    446. [Safe](https://developer.mozilla.org/en-US/docs/Glossary/Safe)
      1. [Safe (HTTP Methods)](https://developer.mozilla.org/en-US/docs/Glossary/Safe/HTTP)
    447. [Salt](https://developer.mozilla.org/en-US/docs/Glossary/Salt)
    448. [Same-origin policy](https://developer.mozilla.org/en-US/docs/Glossary/Same-origin_policy)
    449. [SCM](https://developer.mozilla.org/en-US/docs/Glossary/SCM)
    450. [Scope](https://developer.mozilla.org/en-US/docs/Glossary/Scope)
    451. [Screen reader](https://developer.mozilla.org/en-US/docs/Glossary/Screen_reader)
    452. [Script-supporting element](https://developer.mozilla.org/en-US/docs/Glossary/Script-supporting_element)
    453. [Scroll boundary](https://developer.mozilla.org/en-US/docs/Glossary/Scroll_boundary)
    454. [Scroll chaining](https://developer.mozilla.org/en-US/docs/Glossary/Scroll_chaining)
    455. [Scroll container](https://developer.mozilla.org/en-US/docs/Glossary/Scroll_container)
    456. [Scroll snap](https://developer.mozilla.org/en-US/docs/Glossary/Scroll_snap)
    457. [SCTP](https://developer.mozilla.org/en-US/docs/Glossary/SCTP)
    458. [SDK (Software Development Kit)](https://developer.mozilla.org/en-US/docs/Glossary/SDK)
    459. [SDP](https://developer.mozilla.org/en-US/docs/Glossary/SDP)
    460. [Search engine](https://developer.mozilla.org/en-US/docs/Glossary/Search_engine)
    461. [Secure context](https://developer.mozilla.org/en-US/docs/Glossary/Secure_Context)
    462. [Secure Sockets Layer (SSL)](https://developer.mozilla.org/en-US/docs/Glossary/SSL)
    463. [Selector (CSS)](https://developer.mozilla.org/en-US/docs/Glossary/CSS_Selector)
    464. [Semantics](https://developer.mozilla.org/en-US/docs/Glossary/Semantics)
    465. [SEO](https://developer.mozilla.org/en-US/docs/Glossary/SEO)
    466. [Serializable object](https://developer.mozilla.org/en-US/docs/Glossary/Serializable_object)
    467. [Serialization](https://developer.mozilla.org/en-US/docs/Glossary/Serialization)
    468. [Server](https://developer.mozilla.org/en-US/docs/Glossary/Server)
    469. [Server Timing](https://developer.mozilla.org/en-US/docs/Glossary/Server_Timing)
    470. [Server-side rendering (SSR)](https://developer.mozilla.org/en-US/docs/Glossary/SSR)
    471. [Session hijacking](https://developer.mozilla.org/en-US/docs/Glossary/Session_Hijacking)
    472. [SGML](https://developer.mozilla.org/en-US/docs/Glossary/SGML)
    473. [Shadow tree](https://developer.mozilla.org/en-US/docs/Glossary/Shadow_tree)
    474. [Shallow copy](https://developer.mozilla.org/en-US/docs/Glossary/Shallow_copy)
    475. [Shim](https://developer.mozilla.org/en-US/docs/Glossary/Shim)
    476. [Signature](https://developer.mozilla.org/en-US/docs/Glossary/Signature)
      1. [Signature (functions)](https://developer.mozilla.org/en-US/docs/Glossary/Signature/Function)
      2. [Signature (security)](https://developer.mozilla.org/en-US/docs/Glossary/Signature/Security)
    477. [SIMD](https://developer.mozilla.org/en-US/docs/Glossary/SIMD)
    478. [SISD](https://developer.mozilla.org/en-US/docs/Glossary/SISD)
    479. [Site](https://developer.mozilla.org/en-US/docs/Glossary/Site)
    480. [Site map](https://developer.mozilla.org/en-US/docs/Glossary/Site_map)
    481. [SLD](https://developer.mozilla.org/en-US/docs/Glossary/SLD)
    482. [Sloppy mode](https://developer.mozilla.org/en-US/docs/Glossary/Sloppy_mode)
    483. [Slug](https://developer.mozilla.org/en-US/docs/Glossary/Slug)
    484. [Smoke test](https://developer.mozilla.org/en-US/docs/Glossary/Smoke_Test)
    485. [SMPTE (Society of Motion Picture and Television Engineers)](https://developer.mozilla.org/en-US/docs/Glossary/SMPTE)
    486. [SMTP](https://developer.mozilla.org/en-US/docs/Glossary/SMTP)
    487. [Snake case](https://developer.mozilla.org/en-US/docs/Glossary/Snake_case)
    488. [Snap positions](https://developer.mozilla.org/en-US/docs/Glossary/Snap_positions)
    489. [SOAP](https://developer.mozilla.org/en-US/docs/Glossary/SOAP)
    490. [Social engineering](https://developer.mozilla.org/en-US/docs/Glossary/Social_engineering)
    491. [Source map](https://developer.mozilla.org/en-US/docs/Glossary/Source_map)
    492. [SPA (Single-page application)](https://developer.mozilla.org/en-US/docs/Glossary/SPA)
    493. [Specification](https://developer.mozilla.org/en-US/docs/Glossary/Specification)
    494. [Speculative parsing](https://developer.mozilla.org/en-US/docs/Glossary/Speculative_parsing)
    495. [Speed index](https://developer.mozilla.org/en-US/docs/Glossary/Speed_index)
    496. [SQL](https://developer.mozilla.org/en-US/docs/Glossary/SQL)
    497. [SQL injection](https://developer.mozilla.org/en-US/docs/Glossary/SQL_Injection)
    498. [SRI](https://developer.mozilla.org/en-US/docs/Glossary/SRI)
    499. [Stacking context](https://developer.mozilla.org/en-US/docs/Glossary/Stacking_context)
    500. [State machine](https://developer.mozilla.org/en-US/docs/Glossary/State_machine)
    501. [Statement](https://developer.mozilla.org/en-US/docs/Glossary/Statement)
    502. [Static method](https://developer.mozilla.org/en-US/docs/Glossary/Static_method)
    503. [Static site generator (SSG)](https://developer.mozilla.org/en-US/docs/Glossary/SSG)
    504. [Static typing](https://developer.mozilla.org/en-US/docs/Glossary/Static_typing)
    505. [Sticky activation](https://developer.mozilla.org/en-US/docs/Glossary/Sticky_activation)
    506. [Strict mode](https://developer.mozilla.org/en-US/docs/Glossary/Strict_mode)
    507. [String](https://developer.mozilla.org/en-US/docs/Glossary/String)
    508. [Stringifier](https://developer.mozilla.org/en-US/docs/Glossary/Stringifier)
    509. [STUN](https://developer.mozilla.org/en-US/docs/Glossary/STUN)
    510. [Style origin](https://developer.mozilla.org/en-US/docs/Glossary/Style_origin)
    511. [Style sheet](https://developer.mozilla.org/en-US/docs/Glossary/Style_sheet)
    512. [Submit button](https://developer.mozilla.org/en-US/docs/Glossary/Submit_button)
    513. [SVG](https://developer.mozilla.org/en-US/docs/Glossary/SVG)
    514. [SVN](https://developer.mozilla.org/en-US/docs/Glossary/SVN)
    515. [Symbol](https://developer.mozilla.org/en-US/docs/Glossary/Symbol)
    516. [Symmetric-key cryptography](https://developer.mozilla.org/en-US/docs/Glossary/Symmetric-key_cryptography)
    517. [Synchronous](https://developer.mozilla.org/en-US/docs/Glossary/Synchronous)
    518. [Syntax](https://developer.mozilla.org/en-US/docs/Glossary/Syntax)
    519. [Syntax error](https://developer.mozilla.org/en-US/docs/Glossary/Syntax_error)
    520. [Synthetic monitoring](https://developer.mozilla.org/en-US/docs/Glossary/Synthetic_monitoring)
    521. [Table grid box](https://developer.mozilla.org/en-US/docs/Glossary/Table_Grid_Box)
    522. [Table wrapper box](https://developer.mozilla.org/en-US/docs/Glossary/Table_Wrapper_Box)
    523. [Tag](https://developer.mozilla.org/en-US/docs/Glossary/Tag)
    524. [TCP](https://developer.mozilla.org/en-US/docs/Glossary/TCP)
    525. [TCP handshake](https://developer.mozilla.org/en-US/docs/Glossary/TCP_handshake)
    526. [TCP slow start](https://developer.mozilla.org/en-US/docs/Glossary/TCP_slow_start)
    527. [Telnet](https://developer.mozilla.org/en-US/docs/Glossary/Telnet)
    528. [Texel](https://developer.mozilla.org/en-US/docs/Glossary/Texel)
    529. [The Khronos Group](https://developer.mozilla.org/en-US/docs/Glossary/Khronos)
    530. [Thread](https://developer.mozilla.org/en-US/docs/Glossary/Thread)
    531. [Three js](https://developer.mozilla.org/en-US/docs/Glossary/Three_js)
    532. [Throttle](https://developer.mozilla.org/en-US/docs/Glossary/Throttle)
    533. [Time to First Byte (TTFB)](https://developer.mozilla.org/en-US/docs/Glossary/Time_to_first_byte)
    534. [Time to Interactive (TTI)](https://developer.mozilla.org/en-US/docs/Glossary/Time_to_interactive)
    535. [TLD](https://developer.mozilla.org/en-US/docs/Glossary/TLD)
    536. [TOFU](https://developer.mozilla.org/en-US/docs/Glossary/TOFU)
    537. [Top layer](https://developer.mozilla.org/en-US/docs/Glossary/Top_layer)
    538. [Transient activation](https://developer.mozilla.org/en-US/docs/Glossary/Transient_activation)
    539. [Transport Layer Security (TLS)](https://developer.mozilla.org/en-US/docs/Glossary/TLS)
    540. [Tree shaking](https://developer.mozilla.org/en-US/docs/Glossary/Tree_shaking)
    541. [Trident](https://developer.mozilla.org/en-US/docs/Glossary/Trident)
    542. [Truthy](https://developer.mozilla.org/en-US/docs/Glossary/Truthy)
    543. [TTL](https://developer.mozilla.org/en-US/docs/Glossary/TTL)
    544. [TURN](https://developer.mozilla.org/en-US/docs/Glossary/TURN)
    545. [Type](https://developer.mozilla.org/en-US/docs/Glossary/Type)
    546. [Type coercion](https://developer.mozilla.org/en-US/docs/Glossary/Type_coercion)
    547. [Type conversion](https://developer.mozilla.org/en-US/docs/Glossary/Type_Conversion)
    548. [TypeScript](https://developer.mozilla.org/en-US/docs/Glossary/TypeScript)
    549. [UAAG](https://developer.mozilla.org/en-US/docs/Glossary/UAAG)
    550. [UDP (User Datagram Protocol)](https://developer.mozilla.org/en-US/docs/Glossary/UDP)
    551. [UI](https://developer.mozilla.org/en-US/docs/Glossary/UI)
    552. [Undefined](https://developer.mozilla.org/en-US/docs/Glossary/Undefined)
    553. [Unicode](https://developer.mozilla.org/en-US/docs/Glossary/Unicode)
    554. [Unix time](https://developer.mozilla.org/en-US/docs/Glossary/Unix_time)
    555. [URI](https://developer.mozilla.org/en-US/docs/Glossary/URI)
    556. [URL](https://developer.mozilla.org/en-US/docs/Glossary/URL)
    557. [URN](https://developer.mozilla.org/en-US/docs/Glossary/URN)
    558. [Usenet](https://developer.mozilla.org/en-US/docs/Glossary/Usenet)
    559. [User agent](https://developer.mozilla.org/en-US/docs/Glossary/User_agent)
    560. [UTF-8](https://developer.mozilla.org/en-US/docs/Glossary/UTF-8)
    561. [UTF-16](https://developer.mozilla.org/en-US/docs/Glossary/UTF-16)
    562. [UUID](https://developer.mozilla.org/en-US/docs/Glossary/UUID)
    563. [UX](https://developer.mozilla.org/en-US/docs/Glossary/UX)
    564. [Validator](https://developer.mozilla.org/en-US/docs/Glossary/Validator)
    565. [Value](https://developer.mozilla.org/en-US/docs/Glossary/Value)
    566. [Variable](https://developer.mozilla.org/en-US/docs/Glossary/Variable)
    567. [Vendor prefix](https://developer.mozilla.org/en-US/docs/Glossary/Vendor_Prefix)
    568. [Viewport](https://developer.mozilla.org/en-US/docs/Glossary/Viewport)
    569. [Visual viewport](https://developer.mozilla.org/en-US/docs/Glossary/Visual_Viewport)
    570. [Void element](https://developer.mozilla.org/en-US/docs/Glossary/Void_element)
    571. [VoIP](https://developer.mozilla.org/en-US/docs/Glossary/VoIP)
    572. [W3C](https://developer.mozilla.org/en-US/docs/Glossary/W3C)
    573. [WAI](https://developer.mozilla.org/en-US/docs/Glossary/WAI)
    574. [WCAG](https://developer.mozilla.org/en-US/docs/Glossary/WCAG)
    575. [Web performance](https://developer.mozilla.org/en-US/docs/Glossary/Web_performance)
    576. [Web server](https://developer.mozilla.org/en-US/docs/Glossary/Web_server)
    577. [Web standards](https://developer.mozilla.org/en-US/docs/Glossary/Web_standards)
    578. [WebAssembly](https://developer.mozilla.org/en-US/docs/Glossary/WebAssembly)
    579. [WebDAV](https://developer.mozilla.org/en-US/docs/Glossary/WebDAV)
    580. [WebExtensions](https://developer.mozilla.org/en-US/docs/Glossary/WebExtensions)
    581. [WebGL](https://developer.mozilla.org/en-US/docs/Glossary/WebGL)
    582. [WebIDL](https://developer.mozilla.org/en-US/docs/Glossary/WebIDL)
    583. [WebKit](https://developer.mozilla.org/en-US/docs/Glossary/WebKit)
    584. [WebM](https://developer.mozilla.org/en-US/docs/Glossary/WebM)
    585. [WebP](https://developer.mozilla.org/en-US/docs/Glossary/WebP)
    586. [WebRTC](https://developer.mozilla.org/en-US/docs/Glossary/WebRTC)
    587. [WebSockets](https://developer.mozilla.org/en-US/docs/Glossary/WebSockets)
    588. [WebVTT](https://developer.mozilla.org/en-US/docs/Glossary/WebVTT)
    589. [WHATWG](https://developer.mozilla.org/en-US/docs/Glossary/WHATWG)
    590. [Whitespace](https://developer.mozilla.org/en-US/docs/Glossary/Whitespace)
    591. [WindowProxy](https://developer.mozilla.org/en-US/docs/Glossary/WindowProxy)
    592. [World Wide Web](https://developer.mozilla.org/en-US/docs/Glossary/World_Wide_Web)
    593. [Wrapper](https://developer.mozilla.org/en-US/docs/Glossary/Wrapper)
    594. [XForms](https://developer.mozilla.org/en-US/docs/Glossary/XForms)
    595. [XHTML](https://developer.mozilla.org/en-US/docs/Glossary/XHTML)
    596. [XInclude](https://developer.mozilla.org/en-US/docs/Glossary/XInclude)
    597. [XLink](https://developer.mozilla.org/en-US/docs/Glossary/XLink)
    598. [XML](https://developer.mozilla.org/en-US/docs/Glossary/XML)
    599. [XMLHttpRequest (XHR)](https://developer.mozilla.org/en-US/docs/Glossary/XMLHttpRequest)
    600. [XPath](https://developer.mozilla.org/en-US/docs/Glossary/XPath)
    601. [XQuery](https://developer.mozilla.org/en-US/docs/Glossary/XQuery)
    602. [XSLT](https://developer.mozilla.org/en-US/docs/Glossary/XSLT)
    603. [Zstandard compression](https://developer.mozilla.org/en-US/docs/Glossary/Zstandard_compression)

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