Terms starting with letter a

Color key: WebIDL CSS Markup HTTP

a (value for type attribute of ol element ) §: Defined in HTML
a (markup element) §: Defined in HTML; Referenced in CSS Linked Parameters, CSS Overflow 5, execCommand, Attribution Reporting, Speculation Rules, Content Security Policy 3, CSS Syntax 3, CSS Transforms 2, EPUB 3.3, File API, HTML Accessibility API Mappings 1.0, ARIA in HTML, Publication Manifest, Referrer Policy, Resource Timing, Selectors 4, SVG 2, WAI-ARIA, WAI-ARIA, WebDriver; Related terms: markup attribute charset, markup attribute coords, markup attribute methods, markup attribute name, markup attribute rev, markup attribute shape, markup attribute urn
a (CSS value for lab() ) §: Defined in CSS Color 5; Referenced in CSS Extensions, Filter Effects 1, Selectors 4
a (CSS value for oklab() ) §: Defined in CSS Color 5
a (markup element) §: Defined in SVG 2; Related terms: markup attribute requiredExtensions, markup attribute systemLanguage, markup attribute xlink:href, markup attribute xlink:title
CSSLab.a (WebIDL attribute) §: Defined in CSS Typed OM 1
CSSOKLab.a (WebIDL attribute) §: Defined in CSS Typed OM 1
DOMMatrix.a (WebIDL attribute) §
DOMMatrixReadOnly.a (WebIDL attribute) §: Defined in Geometry Interfaces 1
DOMMatrix2DInit.a (WebIDL dictionary member) §: Defined in Geometry Interfaces 1
GPUColorDict.a (WebIDL dictionary member) §: Defined in WebGPU
MLBinarySupportLimits.a (WebIDL dictionary member) §: Defined in Web Neural Network API
MLGemmSupportLimits.a (WebIDL dictionary member) §: Defined in Web Neural Network API
MLLogicalNotSupportLimits.a (WebIDL dictionary member) §: Defined in Web Neural Network API
A (value for type attribute of ol element ) §: Defined in HTML
a known definite encoding (concept) §: Defined in HTML; Referenced in XMLHttpRequest
a new promise (concept) §: Defined in Web IDL; Referenced in DOM, Fetch, File System, WebXR Anchors, Notifications API, Topics API, requestStorageAccessFor API, Extending Storage Access API to non-cookie storage, The Storage Access API, Storage, Streams, Source Map, Long Animation Frames API, WebAssembly JavaScript Interface: Content Security Policy, WebAssembly JavaScript Interface: ESM Integration, WebAssembly JavaScript Interface: Exception Handling, WebAssembly JavaScript Interface: Promise Integration, WebAssembly JavaScript Interface: JS String Builtins, WebAssembly JavaScript Interface: Type Reflection, Web Bluetooth, Web Bluetooth Scanning, Cookie Store API, Direct Sockets API, EyeDropper API, Fenced Frame, File System Access, Handwriting Recognition API, Idle Detection API, JS Self-Profiling API, Local Font Access, Prerendering Revamped, Observable, Relinquishing Permissions, Prioritized Task Scheduling, Web Serial API, Storage Buckets API, Private State Token API, Protected Audience, User-Agent Client Hints, Web Preferences API, Web Smart Card API, WebHID API, Badging API, Battery Status API, Clipboard API and events, Compute Pressure 1, Contact Picker API, Credential Management 1, CSS View Transitions 1, Gamepad, Indexed DB 3.0, Device Orientation and Motion, Payment Request API, Permissions, Picture-in-Picture, Pointer Lock 2.0, Push API, Screen Orientation, Screen Wake Lock API, Service Workers, WebAssembly JavaScript Interface, WebAssembly Web API, Web Animations, Web Animations 2, Web Locks API, Web Share API, Web Authentication, WebDriver, WebGPU, Web Neural Network API, WebRTC Encoded Transform, WebXR Hit Test, WebXR Lighting Estimation API 1, WebXR Device API, Window Management
a priori authenticated URL (concept) §: Defined in Mixed Content; Referenced in HTML, Clear Site Data, Secure Contexts
a promise rejected with (concept) §: Defined in Web IDL; Referenced in Fetch, File System, HTML, Private Aggregation API, Streams, Web Bluetooth, Cookie Store API, Digital Goods API, File System Access, Idle Detection API, JS Self-Profiling API, Prerendering Revamped, Requesting Permissions, Relinquishing Permissions, Shared Storage API, Storage Buckets API, Web Preferences API, Badging API, Compute Pressure 1, Contact Picker API, Credential Management 1, Federated Credential Management API, Gamepad, MediaStream Image Capture, Indexed DB 3.0, MediaStreamTrack Insertable Media Processing using Streams, Media Session, Payment Request API, Permissions, Screen Orientation, Screen Wake Lock API, Secure Payment Confirmation, Service Workers, Web Locks API, Web Share API, Web Audio API, Web Authentication, WebCodecs, WebGPU, WebTransport
a promise resolved with (concept) §: Defined in Web IDL; Referenced in File System, HTML, Streams, Digital Goods API, Direct Sockets API, File System Access, Web Serial API, Credential Management 1, CSS View Transitions 1, MediaStreamTrack Insertable Media Processing using Streams, Screen Wake Lock API, Service Workers, Web Animations, Web Authentication, WebRTC Encoded Transform, WebTransport
"a-rate" (value for AutomationRate WebIDL enumeration) §: Defined in Web Audio API
a1lx (concept for AV1LayeredImageIndexingProperty ) §: Defined in AVIF
a1op (concept for OperatingPointSelectorProperty ) §: Defined in AVIF
A3 (CSS value for <page-size> ) §: Defined in CSS Paged Media 3
A4 (CSS value for <page-size> ) §: Defined in CSS Paged Media 3
A5 (CSS value for <page-size> ) §: Defined in CSS Paged Media 3
a98-rgb (CSS value for color() ) §: Defined in CSS Color 4; Referenced in CSS Color 5
"aac" (value for AacBitstreamFormat WebIDL enumeration) §: Defined in AAC WebCodecs Registration
AudioEncoderConfig.aac (WebIDL dictionary member) §: Defined in AAC WebCodecs Registration
AacBitstreamFormat (WebIDL enumeration) §: Defined in AAC WebCodecs Registration; Related terms: value aac, value adts; see also WebIDLPedia
AacEncoderConfig (WebIDL dictionary) §: Defined in AAC WebCodecs Registration; Related terms: AacEncoderConfig.format; see also WebIDLPedia
abbr (markup element) §: Defined in HTML; Referenced in HTML Accessibility API Mappings 1.0, ARIA in HTML; Related terms: markup attribute title
abbr (markup attribute for th ) §: Defined in HTML; Referenced in HTML Accessibility API Mappings 1.0
abbr (markup attribute for td ) §: Defined in HTML
HTMLTableCellElement.abbr (WebIDL attribute) §: Defined in HTML
Abjad (concept) §: Defined in Internationalization Glossary
abort (event for AbortSignal ) §: Defined in DOM; Referenced in Observable
abort (concept for fetch controller ) §: Defined in Fetch; Referenced in HTML, Prefetch, Speculation Rules, Protected Audience, Service Workers, XMLHttpRequest
abort (event for HTMLMediaElement ) §: Defined in HTML
abort (concept for WritableStream ) §: Defined in Streams; Referenced in Direct Sockets API, Web Serial API
abort (event for FileReader ) §: Defined in File API
abort (event for IDBTransaction ) §: Defined in Indexed DB 3.0
abort (event) §: Defined in Media Source Extensions™
abort (event for XMLHttpRequestEventTarget ) §: Defined in XMLHttpRequest
ObservableInspector.abort (WebIDL dictionary member) §: Defined in Observable
UnderlyingSink.abort (WebIDL dictionary member) §: Defined in Streams
abort a running script (concept) §: Defined in HTML; Referenced in Service Workers
abort reason (concept for AbortSignal ) §: Defined in DOM; Referenced in Fetch, Streams, Web NFC API, Direct Sockets API, EyeDropper API, Idle Detection API, Observable, Prioritized Task Scheduling, Web Serial API, Protected Audience, Web Smart Card API, Credential Management 1, Geolocation Sensor, Web Locks API, Web Authentication, WebTransport
Abort the fetch() call (concept) §: Defined in Fetch
abort the update (concept) §: Defined in Payment Request API
abort when (concept) §: Defined in Infra; Referenced in Fetch, Private Aggregation API, Web Bluetooth, Background Fetch, Service Workers, WebDriver, WebTransport
DOMException.ABORT_ERR (WebIDL constant) §: Defined in Web IDL
BackgroundFetchRegistration.abort() (WebIDL operation) §: Defined in Background Fetch
FileReader.abort() (WebIDL operation) §: Defined in File API
IDBTransaction.abort() (WebIDL operation) §: Defined in Indexed DB 3.0
PaymentRequest.abort() (WebIDL operation) §: Defined in Payment Request API
SourceBuffer.abort() (WebIDL operation) §: Defined in Media Source Extensions™
SpeechRecognition.abort() (WebIDL operation) §: Defined in Web Speech API; Referenced in Prerendering Revamped
XMLHttpRequest.abort() (WebIDL operation) §: Defined in XMLHttpRequest
AbortController.abort(reason) (WebIDL operation) §: Defined in DOM
AbortSignal.abort(reason) (WebIDL operation) §: Defined in DOM
WritableStream.abort(reason) (WebIDL operation) §: Defined in Streams; Referenced in Direct Sockets API, Web Serial API, WebTransport
WritableStreamDefaultWriter.abort(reason) (WebIDL operation) §: Defined in Streams; Referenced in Direct Sockets API, Web Serial API, WebTransport
abortAlgorithm (concept for set up of WritableStream interface ) §: Defined in Streams; Referenced in File System, Direct Sockets API, Web Serial API, MediaStreamTrack Insertable Media Processing using Streams, WebTransport
AbortController (WebIDL interface) §: Defined in DOM; Referenced in HTML, Streams, Web Bluetooth, Observable, Prioritized Task Scheduling, Service Workers, Web Authentication, WebRTC Encoded Transform; Related terms: concept signal, concept signal abort, AbortController.signal, new AbortController(), AbortController.abort(reason); see also WebIDLPedia
new AbortController() (WebIDL constructor) §: Defined in DOM
aborted (concept for AbortSignal ) §: Defined in DOM; Referenced in Fetch, HTML, Streams, Web NFC API, Web Bluetooth, Direct Sockets API, Idle Detection API, Observable, Prioritized Task Scheduling, Web Serial API, Protected Audience, Web Smart Card API, Credential Management 1, Geolocation Sensor, Web Locks API, Web Authentication, WebRTC Encoded Transform
"aborted" (value for BackgroundFetchFailureReason WebIDL enumeration) §: Defined in Background Fetch
"aborted" (value for SpeechRecognitionErrorCode WebIDL enumeration) §: Defined in Web Speech API
AbortSignal.aborted (WebIDL attribute) §: Defined in DOM; Referenced in EyeDropper API
aborted flag (concept for response ) §: Defined in Fetch; Referenced in Service Workers, XMLHttpRequest
aborted network error (concept) §: Defined in Fetch; Referenced in HTML, Background Fetch
AbortError (exception) §: Defined in Web IDL; Referenced in DOM, Fetch, File System, HTML, Web NFC API, Web Bluetooth, EyeDropper API, File System Access, Web Smart Card API, WebHID API, WebUSB API, Audio Output Devices API, Compute Pressure 1, CSS View Transitions 1, CSS View Transitions 2, Indexed DB 3.0, Media Capture and Streams, Viewport Capture, Payment Request API, Push API, Screen Capture, Screen Orientation, Service Workers, Web Animations, Web Locks API, Web Share API, Web Authentication, WebCodecs, WebGPU, Web MIDI API, WebTransport, WebXR Device API, XMLHttpRequest
AbortSignal (WebIDL interface) §: Defined in DOM; Referenced in Fetch, HTML, Streams, Web NFC API, Web Bluetooth, EyeDropper API, Idle Detection API, Observable, Prioritized Task Scheduling, Protected Audience, Web Smart Card API, Credential Management 1, Geolocation Sensor, Web Locks API, Web Authentication; Related terms: concept abort reason, concept aborted, concept add, concept onabort, concept remove, AbortSignal.aborted, AbortSignal.onabort, AbortSignal.reason, event abort, AbortSignal.abort(reason), AbortSignal.any(signals), AbortSignal.throwIfAborted(), AbortSignal.timeout(milliseconds); see also WebIDLPedia
[[AbortSteps]] (algorithm for WritableStreamDefaultController ) §: Defined in Streams
[[AbortSteps]] (algorithm for WritableStreamController ) §: Defined in Streams
abrupt completion (concept for ECMAScript ) §: Defined in ECMAScript
MLOpSupportLimits.abs (WebIDL dictionary member) §: Defined in Web Neural Network API
abs() (CSS function) §: Defined in CSS Values 4
MLGraphBuilder.abs(input, options) (WebIDL operation) §: Defined in Web Neural Network API
Math.abs(x) (WebIDL operation) §: Defined in ECMAScript
"absent" (value for SmartCardConnectionState WebIDL enumeration) §: Defined in Web Smart Card API
absolute (CSS value for position ) §: Defined in CSS Positioned Layout 3 , CSS 2.2; Referenced in CSS Positioned Layout 4, Quirks Mode, CSS Scroll Anchoring 1, WebVTT: The Web Video Text Tracks Format
absolute (CSS value for voice-pitch ) §: Defined in CSS Speech 1; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
absolute (CSS value for voice-range ) §: Defined in CSS Speech 1; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
DeviceOrientationEvent.absolute (WebIDL attribute) §: Defined in Device Orientation and Motion
DeviceOrientationEventInit.absolute (WebIDL dictionary member) §: Defined in Device Orientation and Motion
absolute color (concept) §: Defined in CSS Color 4 , CSS Color 5; Referenced in CSS Fonts 4
absolute length (concept) §: Defined in CSS 2.1
absolute position (concept) §: Defined in CSS Positioned Layout 3; Referenced in CSS Display 4, CSS Positioned Layout 4, CSS Box Alignment 3, CSS Anchor Positioning, CSS Grid Layout 2, CSS Inline Layout 3, CSS Sizing 4, Scroll-driven Animations
absolute positioning containing block (concept) §: Defined in CSS Positioned Layout 3; Referenced in CSS Containment 1, CSS Containment 2, CSS View Transitions 1
absolute positioning layout (concept) §: Defined in CSS Positioned Layout 3
absolute-colorimetric (CSS value for rendering-intent descriptor of @color-profile @rule ) §: Defined in CSS Color 5
absolute-orientation virtual sensor type (concept) §: Defined in Device Orientation and Motion; Referenced in Orientation Sensor
absolute-position containing block (concept) §: Defined in CSS Positioned Layout 3
<absolute-size> (CSS type) §: Defined in CSS 2.2; Referenced in CSS Fonts 4, CSS Typed OM 1
absolute-URL string (concept) §: Defined in URL; Referenced in Network Reporting API, Web NFC API, CSSOM, EPUB 3.3, Payment Method Manifest, Publication Manifest, Verifiable Credentials Data Model v2.0
absolute-URL-with-fragment string (concept) §: Defined in URL; Referenced in Fetch, EPUB 3.3, Publication Manifest
absolutely positioned element (concept) §: Defined in CSS 2.1; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
AbsoluteOrientationSensor (WebIDL interface) §: Defined in Orientation Sensor; Related terms: new AbsoluteOrientationSensor(sensorOptions); see also WebIDLPedia
new AbsoluteOrientationSensor(sensorOptions) (WebIDL constructor) §: Defined in Orientation Sensor
Abstract Closure (concept for ECMAScript ) §: Defined in ECMAScript; Referenced in HTML, 2022, ECMAScript Async Explicit Resource Management, ECMAScript Explicit Resource Management, Iterator Helpers, JSON modules, Regular Expression Pattern Modifiers for ECMAScript, Source Phase Imports, Web IDL
abstract dimensions (concept) §: Defined in CSS Writing Modes 3 , CSS Writing Modes 4; Referenced in CSS Snapshot 2022, CSS Snapshot 2023, CSS Layout API 1
abstract operation HostGrowSharedArrayBuffer (concept) §: Defined in WebAssembly JavaScript Interface: Threading
abstract operation HostResizeArrayBuffer (concept) §: Defined in WebAssembly JavaScript Interface: ESM Integration , WebAssembly JavaScript Interface: JS String Builtins , WebAssembly JavaScript Interface: Threading , WebAssembly JavaScript Interface
AbstractRange (WebIDL interface) §: Defined in DOM; Referenced in CSS Custom Highlight API 1; Related terms: AbstractRange.collapsed, AbstractRange.endContainer, AbstractRange.endOffset, AbstractRange.startContainer, AbstractRange.startOffset; see also WebIDLPedia
AbstractWorker (WebIDL interface) §: Defined in HTML; Referenced in Service Workers; Related terms: AbstractWorker.onerror, event error; see also WebIDLPedia
Abugida (concept) §: Defined in Internationalization Glossary
DeviceMotionEvent.acceleration (WebIDL attribute) §: Defined in Device Orientation and Motion
DeviceMotionEventInit.acceleration (WebIDL dictionary member) §: Defined in Device Orientation and Motion
DeviceMotionEvent.accelerationIncludingGravity (WebIDL attribute) §: Defined in Device Orientation and Motion
DeviceMotionEventInit.accelerationIncludingGravity (WebIDL dictionary member) §: Defined in Device Orientation and Motion
Accelerometer (WebIDL interface) §: Defined in Accelerometer; Referenced in Orientation Sensor; Related terms: Accelerometer.x, Accelerometer.y, Accelerometer.z, new Accelerometer(options); see also WebIDLPedia
"accelerometer" (permission name) §: Defined in Device Orientation and Motion; Referenced in Accelerometer
accelerometer virtual sensor type (concept) §: Defined in Device Orientation and Motion; Referenced in Accelerometer
new Accelerometer(options) (WebIDL constructor) §: Defined in Accelerometer
AccelerometerLocalCoordinateSystem (WebIDL enumeration) §: Defined in Accelerometer; Related terms: value device, value screen; see also WebIDLPedia
AccelerometerSensorOptions (WebIDL dictionary) §: Defined in Accelerometer; Related terms: AccelerometerSensorOptions.referenceFrame; see also WebIDLPedia
accent (markup attribute for mover, munder element, munderover element ) §: Defined in MathML Core
accent-color (CSS property) §: Defined in CSS User Interface 4; Referenced in CSS Color Adjustment 1, CSS Text Decoration 4; Related terms: CSS value auto
AccentColor (CSS value for <color>, <system-color> type ) §: Defined in CSS Color 4
AccentColorText (CSS value for <color>, <system-color> type ) §: Defined in CSS Color 4
accentunder (markup attribute for mover, munder element, munderover element ) §: Defined in MathML Core
accept (markup attribute for input ) §: Defined in HTML; Referenced in HTML Accessibility API Mappings 1.0, HTML Media Capture
accept (markup attribute for form ) §: Defined in HTML
FilePickerAcceptType.accept (WebIDL dictionary member) §: Defined in File System Access
HTMLInputElement.accept (WebIDL attribute) §: Defined in HTML; Referenced in File and Directory Entries API
Accept-CH cache (concept) §: Defined in Client Hints Infrastructure; Referenced in Clear Site Data
accept-charset (markup attribute for form ) §: Defined in HTML; Referenced in HTML Accessibility API Mappings 1.0
acceptable anchor element (concept) §: Defined in CSS Anchor Positioning
BluetoothLEScan.acceptAllAdvertisements (WebIDL attribute) §: Defined in Web Bluetooth Scanning
BluetoothLEScanOptions.acceptAllAdvertisements (WebIDL dictionary member) §: Defined in Web Bluetooth Scanning
BluetoothLEScanPermissionDescriptor.acceptAllAdvertisements (WebIDL dictionary member) §: Defined in Web Bluetooth Scanning
BluetoothPermissionDescriptor.acceptAllDevices (WebIDL dictionary member) §: Defined in Web Bluetooth
RequestDeviceOptions.acceptAllDevices (WebIDL dictionary member) §: Defined in Web Bluetooth
HTMLFormElement.acceptCharset (WebIDL attribute) §: Defined in HTML
"accepted" (value for AppBannerPromptOutcome WebIDL enumeration) §: Defined in Manifest Incubations
accepted @position-try properties (concept) §: Defined in CSS Anchor Positioning
NodeFilter.acceptNode(node) (WebIDL operation) §: Defined in DOM
GPUStorageTextureBindingLayout.access (WebIDL dictionary member) §: Defined in WebGPU
Access-Control-Allow-Credentials: (HTTP header) §: Defined in Fetch; Referenced in requestStorageAccessFor API, Private Network Access, Beacon
Access-Control-Allow-Headers: (HTTP header) §: Defined in Fetch; Referenced in Beacon
Access-Control-Allow-Methods: (HTTP header) §: Defined in Fetch; Referenced in Private Network Access
Access-Control-Allow-Origin: (HTTP header) §: Defined in Fetch; Referenced in Speculation Rules, Private Network Access, Beacon
Access-Control-Allow-Private-Network: (HTTP header) §: Defined in Private Network Access
Access-Control-Expose-Headers: (HTTP header) §: Defined in Fetch
Access-Control-Max-Age: (HTTP header) §: Defined in Fetch
Access-Control-Request-Headers: (HTTP header) §: Defined in Fetch; Referenced in Private Network Access
Access-Control-Request-Method: (HTTP header) §: Defined in Fetch; Referenced in Private Network Access
Access-Control-Request-Private-Network: (HTTP header) §: Defined in Private Network Access
Accessibility API (concept) §: Defined in WAI-ARIA , WAI-ARIA
accessibility child (concept) §: Defined in WAI-ARIA , WAI-ARIA
accessibility descendant (concept) §: Defined in WAI-ARIA , WAI-ARIA
accessibility parent (concept) §: Defined in WAI-ARIA , WAI-ARIA
Accessibility Subtree (concept) §: Defined in Core Accessibility API Mappings 1.2
Accessibility Tree (concept) §: Defined in WAI-ARIA , WAI-ARIA
Accessible Description (concept) §: Defined in Accessible Name and Description Computation 1.2
Accessible Name (concept) §: Defined in Accessible Name and Description Computation 1.2
Accessible object (concept) §: Defined in WAI-ARIA , WAI-ARIA
accesskey (markup attribute for html-global ) §: Defined in HTML; Referenced in HTML Accessibility API Mappings 1.0, SVG 2
HTMLElement.accessKey (WebIDL attribute) §: Defined in HTML
HTMLElement.accessKeyLabel (WebIDL attribute) §: Defined in HTML
accessor property (concept for ECMAScript ) §: Defined in ECMAScript
DisconnectedAccount.account_id (WebIDL dictionary member) §: Defined in Federated Credential Management API
IdentityCredentialDisconnectOptions.accountHint (WebIDL dictionary member) §: Defined in Federated Credential Management API
IdentityProviderAccountList.accounts (WebIDL dictionary member) §: Defined in Federated Credential Management API
IdentityProviderAPIConfig.accounts_endpoint (WebIDL dictionary member) §: Defined in Federated Credential Management API
accumulate (markup attribute for animate ) §: Defined in SVG Animations 2; Referenced in SVG 2
"accumulate" (value for CompositeOperation, CompositeOperationOrAuto enumeration WebIDL enumerations) §: Defined in Web Animations
"accumulate" (value for IterationCompositeOperation WebIDL enumeration) §: Defined in Web Animations 2
accumulation for one-based values (concept) §: Defined in CSS Transforms 2
GeolocationCoordinates.accuracy (WebIDL attribute) §: Defined in Geolocation
GeolocationSensor.accuracy (WebIDL attribute) §: Defined in Geolocation Sensor
GeolocationSensorReading.accuracy (WebIDL dictionary member) §: Defined in Geolocation Sensor
acos() (CSS function) §: Defined in CSS Values 4
Math.acos(x) (WebIDL operation) §: Defined in ECMAScript
Math.acosh(x) (WebIDL operation) §: Defined in ECMAScript
AcquireReadableStreamBYOBReader (algorithm) §: Defined in Streams
AcquireReadableStreamDefaultReader (algorithm) §: Defined in Streams
AcquireWritableStreamDefaultWriter (algorithm) §: Defined in Streams
acronym (markup element) §: Defined in HTML
action (markup attribute for button, form element ) §: Defined in HTML; Referenced in HTML Accessibility API Mappings 1.0, Mixed Content
CaptureActionEvent.action (WebIDL attribute) §: Defined in The Capture-Handle Actions Mechanism
CaptureActionEventInit.action (WebIDL dictionary member) §: Defined in The Capture-Handle Actions Mechanism
HTMLFormElement.action (WebIDL attribute) §: Defined in HTML
MediaSessionActionDetails.action (WebIDL dictionary member) §: Defined in Media Session
NotificationAction.action (WebIDL dictionary member) §: Defined in Notifications API
NotificationEvent.action (WebIDL attribute) §: Defined in Notifications API
NotificationEventInit.action (WebIDL dictionary member) §: Defined in Notifications API
Notification.actions (WebIDL attribute) §: Defined in Notifications API
NotificationOptions.actions (WebIDL dictionary member) §: Defined in Notifications API
actiontype (markup attribute for maction ) §: Defined in MathML Core
activate (event for ServiceWorkerGlobalScope ) §: Defined in Service Workers
Activate a sensor object (concept) §: Defined in Generic Sensor API
HTMLPortalElement.activate(options) (WebIDL operation) §: Defined in Portals
"activated" (value for ServiceWorkerState WebIDL enumeration) §: Defined in Service Workers
Sensor.activated (WebIDL attribute) §: Defined in Generic Sensor API
"activating" (value for ServiceWorkerState WebIDL enumeration) §: Defined in Service Workers
activation (concept for user navigation involvement ) §: Defined in HTML
Navigation.activation (WebIDL attribute) §: Defined in HTML
PageSwapEvent.activation (WebIDL attribute) §: Defined in HTML; Referenced in CSS View Transitions 2
PageSwapEventInit.activation (WebIDL dictionary member) §: Defined in HTML
activation behavior (concept for EventTarget ) §: Defined in DOM; Referenced in HTML, Portals, SVG 2, UI Events
Activation behavior (concept) §: Defined in Core Accessibility API Mappings 1.2
MLGruCellOptions.activations (WebIDL dictionary member) §: Defined in Web Neural Network API
MLGruOptions.activations (WebIDL dictionary member) §: Defined in Web Neural Network API
MLLstmCellOptions.activations (WebIDL dictionary member) §: Defined in Web Neural Network API
MLLstmOptions.activations (WebIDL dictionary member) §: Defined in Web Neural Network API
PerformanceNavigationTiming.activationStart (WebIDL attribute) §: Defined in Prerendering Revamped
:active (CSS selector) §: Defined in CSS 2.2 , Selectors 3 , Selectors 4; Referenced in Quirks Mode, CSS Snapshot 2022, CSS Snapshot 2023
"active" (value for AudioSessionState WebIDL enumeration) §: Defined in Audio Session
"active" (value for UserIdleState WebIDL enumeration) §: Defined in Idle Detection API
"active" (value for ClientLifecycleState WebIDL enumeration) §: Defined in Page Lifecycle
active (CSS value for forced-colors descriptor of @media @rule ) §: Defined in Media Queries 5
active (concept for ExtendableEvent ) §: Defined in Service Workers; Referenced in Background Fetch, WebXR Hand Input 1
"active" (value for AnimationReplaceState WebIDL enumeration) §: Defined in Web Animations
"active" (value for AnimationReplacedState WebIDL enumeration) §: Defined in Web Animations
"active" (value for RTCIceTcpCandidateType WebIDL enumeration) §: Defined in WebRTC 1.0
BluetoothLEScan.active (WebIDL attribute) §: Defined in Web Bluetooth Scanning
MediaStream.active (WebIDL attribute) §: Defined in Media Capture and Streams
RTCOutboundRtpStreamStats.active (WebIDL dictionary member) §: Defined in WebRTC Statistics
RTCRtpEncodingParameters.active (WebIDL dictionary member) §: Defined in WebRTC 1.0
ServiceWorkerRegistration.active (WebIDL attribute) §: Defined in Service Workers
Subscriber.active (WebIDL attribute) §: Defined in Observable
active BiDi sessions (concept) §: Defined in WebDriver BiDi
active browsing context (concept for navigable ) §: Defined in HTML; Referenced in Document Picture-in-Picture, Fenced Frame, Prefetch, Service Workers, WebDriver
VideoDecoder.[[active decoder config]] (internal slot) §: Defined in WebCodecs
active document (concept for navigable ) §: Defined in HTML; Referenced in Compatibility, Fetch, Fullscreen API, Topics API, GPC, Navigational-Tracking Mitigations, requestStorageAccessFor API, The Storage Access API, Long Animation Frames API, WebDriver BiDi, Iframe credentialless, Attribution Reporting, Document Picture-in-Picture, Fenced Frame, Prefetch, Prerendering Revamped, URL Fragment Text Directives, Shared Storage API, Web App Launch Handler API, Web Application Manifest, Clear Site Data, Credential Management 1, CSS Spatial Navigation 1, CSSOM View, Device Posture API, Generic Sensor API, Largest Contentful Paint, Long Tasks API, Mixed Content, Device Orientation and Motion, Permissions Policy, Pointer Lock 2.0, Reporting API, Screen Orientation, Selection API, Service Workers, WebXR Device API, Window Management
AudioEncoder.[[active encoder config]] (internal slot) §: Defined in WebCodecs
VideoEncoder.[[active encoder config]] (internal slot) §: Defined in WebCodecs
active function object (concept for ECMAScript ) §: Defined in ECMAScript; Referenced in HTML, ECMAScript Internationalization API, ECMAScript Async Explicit Resource Management, ECMAScript Explicit Resource Management, Iterator Helpers, JSON.parse source text access, ShadowRealm API
AudioEncoder.[[active output config]] (internal slot) §: Defined in WebCodecs
VideoEncoder.[[active output config]] (internal slot) §: Defined in WebCodecs
active phase (concept for animation effect ) §: Defined in Web Animations; Referenced in CSS Animations 2, Web Animations 2
active sandboxing flag set (concept for Document ) §: Defined in HTML; Referenced in The Storage Access API, Fenced Frame, Prerendering Revamped, Protected Audience, Content Security Policy 3, Pointer Lock 2.0, Presentation API
active script or module (concept for ECMAScript ) §: Defined in ECMAScript; Referenced in Import Attributes, JSON modules, Source Phase Imports
active service worker (concept for environment ) §: Defined in HTML; Referenced in Service Workers
active speculative HTML parser (concept) §: Defined in HTML
active timeline (concept) §: Defined in Web Animations
active window (concept for navigable ) §: Defined in HTML; Referenced in WebDriver BiDi, Document Picture-in-Picture, Prerendering Revamped, Shared Storage API, Device Orientation and Motion, Presentation API, Remote Playback API
active worker (concept for service worker registration ) §: Defined in Service Workers; Referenced in HTML, Notifications API, Background Fetch, Content Index, Web Periodic Background Synchronization
:active-view-transition (CSS selector) §: Defined in CSS View Transitions 2
:active-view-transition-type() (CSS selector) §: Defined in CSS View Transitions 2
BluetoothRemoteGATTServer.[[activeAlgorithms]] (internal slot) §: Defined in Web Bluetooth
ActiveBorder (concept) §: Defined in CSS Color 3; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
ActiveBorder (CSS value for <color>, <deprecated-color> type ) §: Defined in CSS Color 4
ActiveCaption (concept) §: Defined in CSS Color 3; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
ActiveCaption (CSS value for <color>, <deprecated-color> type ) §: Defined in CSS Color 4
TextTrack.activeCues (WebIDL attribute) §: Defined in HTML
ComputedEffectTiming.activeDuration (WebIDL dictionary member) §
ComputedEffectTiming.activeDuration (WebIDL dictionary member) §: Defined in Web Animations , Web Animations 2
DocumentOrShadowRoot.activeElement (WebIDL attribute) §: Defined in HTML
SmartCardConnectResult.activeProtocol (WebIDL dictionary member) §: Defined in Web Smart Card API
Bluetooth.[[activeScans]] (internal slot) §: Defined in Web Bluetooth Scanning
MediaSource.activeSourceBuffers (WebIDL attribute) §: Defined in Media Source Extensions™
ResizeObserver.[[activeTargets]] (internal slot) §: Defined in Resize Observer
ActiveText (CSS value for <color>, <system-color> type ) §: Defined in CSS Color 4
actual value (concept) §: Defined in CSS Cascading 3 , CSS Cascading 4 , CSS Cascading 5; Referenced in CSS Snapshot 2022, CSS Snapshot 2023, CSS Color 5, CSS Values 3, CSS Values 4
actual value (concept) §: Defined in CSS 2.1
TextMetrics.actualBoundingBoxAscent (WebIDL attribute) §: Defined in HTML
TextMetrics.actualBoundingBoxDescent (WebIDL attribute) §: Defined in HTML
TextMetrics.actualBoundingBoxLeft (WebIDL attribute) §: Defined in HTML
TextMetrics.actualBoundingBoxRight (WebIDL attribute) §: Defined in HTML
GenerateBidOutput.ad (WebIDL dictionary member) §: Defined in Protected Audience
Ad-Auction-Additional-Bid: (HTTP header) §: Defined in Protected Audience
Ad-Auction-Allow-Trusted-Scoring-Signals-From: (HTTP header) §: Defined in Protected Audience
Ad-Auction-Allowed: (HTTP header) §: Defined in Protected Audience
Ad-Auction-Signals: (HTTP header) §: Defined in Protected Audience
[[adapter]] (internal slot for device ) §: Defined in WebGPU
GPUAdapter.[[adapter]] (internal slot) §: Defined in WebGPU
Navigator.adAuctionComponents(numAdComponents) (WebIDL operation) §: Defined in Fenced Frame
AdAuctionData (WebIDL dictionary) §: Defined in Protected Audience; Related terms: AdAuctionData.request, AdAuctionData.requestId; see also WebIDLPedia
AdAuctionDataConfig (WebIDL dictionary) §: Defined in Protected Audience; Related terms: AdAuctionDataConfig.coordinatorOrigin, AdAuctionDataConfig.seller; see also WebIDLPedia
HTMLIFrameElement.adAuctionHeaders (WebIDL attribute) §: Defined in Protected Audience
RequestInit.adAuctionHeaders (WebIDL dictionary member) §: Defined in Protected Audience
adauctionheaders (markup attribute for iframe ) §: Defined in Protected Audience
GenerateBidInterestGroup.adComponents (WebIDL dictionary member) §: Defined in Protected Audience
GenerateBidOutput.adComponents (WebIDL dictionary member) §: Defined in Protected Audience
ScoringBrowserSignals.adComponents (WebIDL dictionary member) §: Defined in Protected Audience
BiddingBrowserSignals.adComponentsLimit (WebIDL dictionary member) §: Defined in Protected Audience
GenerateBidOutput.adCost (WebIDL dictionary member) §: Defined in Protected Audience
ReportWinBrowserSignals.adCost (WebIDL dictionary member) §: Defined in Protected Audience
add (concept for AbortSignal ) §: Defined in DOM; Referenced in Fetch, HTML, Streams, Web Bluetooth, Direct Sockets API, EyeDropper API, Idle Detection API, Observable, Prioritized Task Scheduling, Web Serial API, Protected Audience, Web Smart Card API, Geolocation Sensor, Web Locks API, WebRTC Encoded Transform, WebTransport
add (CSS value for mask-composite ) §: Defined in CSS Masking 1; Referenced in CSS Snapshot 2022, CSS Snapshot 2023, CSS Animations 2
"add" (value for CompositeOperation, CompositeOperationOrAuto enumeration WebIDL enumerations) §: Defined in Web Animations
add (algorithm for usage scope ) §: Defined in WebGPU
"add" (value for GPUBlendOperation WebIDL enumeration) §: Defined in WebGPU
MLOpSupportLimits.add (WebIDL dictionary member) §: Defined in Web Neural Network API
add a CSS style sheet (concept) §: Defined in CSSOM
add a range header (concept for request ) §: Defined in Fetch; Referenced in HTML, Background Fetch
add a track (algorithm for MediaStream ) §: Defined in Media Capture and Streams
add an element to the top layer (concept) §: Defined in CSS Positioned Layout 4; Referenced in Fullscreen API, HTML
add an event listener (concept) §: Defined in DOM; Referenced in HTML, Observable, CSSOM View
add lifetime promise (concept for ExtendableEvent ) §: Defined in Service Workers
add mock camera (concept for extension commands ) §: Defined in Media Capture Automation
add mock microphone (concept for extension commands ) §: Defined in Media Capture Automation
add two types (concept for CSSNumericValue ) §: Defined in CSS Typed OM 1; Referenced in CSS Values 4
DOMTokenList.add(...tokens) (WebIDL operation) §: Defined in DOM
CSSNumericValue.add(...values) (WebIDL operation) §: Defined in CSS Typed OM 1
DataTransferItemList.add() (WebIDL operation) §: Defined in HTML
RdfDataset.add() (WebIDL operation) §: Defined in JSON-LD 1.1 Processing Algorithms and API
RdfGraph.add() (WebIDL operation) §: Defined in JSON-LD 1.1 Processing Algorithms and API
MLGraphBuilder.add(a, b, options) (WebIDL operation) §: Defined in Web Neural Network API
ContentIndex.add(description) (WebIDL operation) §: Defined in Content Index
HTMLOptionsCollection.add(element, before) (WebIDL operation) §: Defined in HTML
HTMLSelectElement.add(element, before) (WebIDL operation) §: Defined in HTML
FontFaceSet.add(font) (WebIDL operation) §: Defined in CSS Font Loading 3
Cache.add(request) (WebIDL operation) §: Defined in Service Workers
Atomics.add(typedArray, index, value) (WebIDL operation) §: Defined in ECMAScript
IDBObjectStore.add(value, key) (WebIDL operation) §: Defined in Indexed DB 3.0
add(value) (WebIDL operation for Set ) §: Defined in ECMAScript
WeakSet.add(value) (WebIDL operation) §: Defined in ECMAScript
Cache.addAll(requests) (WebIDL operation) §: Defined in Service Workers
CanvasGradient.addColorStop(offset, color) (WebIDL operation) §: Defined in HTML
TextTrack.addCue(cue) (WebIDL operation) §: Defined in HTML; Referenced in WebVTT: The Web Video Text Tracks Format
XRInputSourcesChangeEvent.added (WebIDL attribute) §: Defined in WebXR Device API
XRInputSourcesChangeEventInit.added (WebIDL dictionary member) §: Defined in WebXR Device API
MutationRecord.addedNodes (WebIDL attribute) §: Defined in DOM
BufferedChangeEvent.addedRanges (WebIDL attribute) §: Defined in Media Source Extensions™
BufferedChangeEventInit.addedRanges (WebIDL dictionary member) §: Defined in Media Source Extensions™
AddEntriesFromIterable (algorithm) §: Defined in ECMAScript
EventTarget.addEventListener(type, callback, options) (WebIDL operation) §: Defined in DOM; Referenced in HTML, CSSOM View, UI Events
AddEventListenerOptions (WebIDL dictionary) §: Defined in DOM; Related terms: AddEventListenerOptions.once, AddEventListenerOptions.passive, AddEventListenerOptions.signal; see also WebIDLPedia
SpeechGrammarList.addFromString(string, weight) (WebIDL operation) §: Defined in Web Speech API
SpeechGrammarList.addFromURI(src, weight) (WebIDL operation) §: Defined in Web Speech API
RTCPeerConnection.addIceCandidate!overload-1() (WebIDL operation) §: Defined in WebRTC 1.0
RTCPeerConnection.addIceCandidate() (WebIDL operation) §: Defined in WebRTC 1.0
additional capability deserialization algorithm (concept) §: Defined in WebDriver; Referenced in WebDriver BiDi
additional-name (value for autocomplete attribute of button element, autocomplete attribute of fieldset element, autocomplete attribute of input element, autocomplete attribute of object element, autocomplete attribute of output element, autocomplete attribute of select element, autocomplete attribute of textarea element ) §: Defined in HTML
AuctionAdInterestGroup.additionalBidKey (WebIDL dictionary member) §: Defined in Protected Audience
AuctionAdConfig.additionalBids (WebIDL dictionary member) §: Defined in Protected Audience
AesGcmParams.additionalData (WebIDL dictionary member) §: Defined in Web Cryptography API
PaymentDetailsModifier.additionalDisplayItems (WebIDL dictionary member) §: Defined in Payment Request API
additive (markup attribute for animate ) §: Defined in SVG Animations 2; Referenced in SVG 2
additive (CSS value for system descriptor of @counter-style @rule ) §: Defined in CSS Counter Styles 3; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
additive (CSS value for environment-blending descriptor of @media @rule ) §: Defined in Media Queries 5
"additive" (value for XREnvironmentBlendMode WebIDL enumeration) §: Defined in WebXR Augmented Reality 1
additive color space (concept) §: Defined in CSS Color 4
additive tuple (concept) §: Defined in CSS Counter Styles 3; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
additive-symbols (CSS descriptor for @counter-style ) §: Defined in CSS Counter Styles 3
CSSCounterStyleRule.additiveSymbols (WebIDL attribute) §: Defined in CSS Counter Styles 3
MediaQueryList.addListener(callback) (WebIDL operation) §: Defined in CSSOM View
Worklet.addModule(moduleURL, options) (WebIDL operation) §: Defined in HTML; Referenced in Private Aggregation API, Shared Storage API, Web Audio API
Path2D.addPath(path, transform) (WebIDL operation) §: Defined in HTML
HandwritingStroke.addPoint(point) (WebIDL operation) §: Defined in Handwriting Recognition API
Selection.addRange() (WebIDL operation) §: Defined in Selection API
RTCIceTransport.addRemoteCandidate() (WebIDL operation) §: Defined in IceTransport Extensions for WebRTC
address (markup element) §: Defined in HTML; Referenced in HTML Accessibility API Mappings 1.0, ARIA in HTML, WebDriver
"address" (value for ContactProperty WebIDL enumeration) §: Defined in Contact Picker API
ContactInfo.address (WebIDL dictionary member) §: Defined in Contact Picker API
RTCIceCandidate.address (WebIDL attribute) §: Defined in WebRTC 1.0
RTCIceCandidateStats.address (WebIDL dictionary member) §: Defined in WebRTC Statistics
RTCPeerConnectionIceErrorEvent.address (WebIDL attribute) §: Defined in WebRTC 1.0
RTCPeerConnectionIceErrorEventInit.address (WebIDL dictionary member) §: Defined in WebRTC 1.0
address line (concept for physical address ) §: Defined in Contact Picker API
address-level1 (value for autocomplete attribute of button element, autocomplete attribute of fieldset element, autocomplete attribute of input element, autocomplete attribute of object element, autocomplete attribute of output element, autocomplete attribute of select element, autocomplete attribute of textarea element ) §: Defined in HTML
address-level2 (value for autocomplete attribute of button element, autocomplete attribute of fieldset element, autocomplete attribute of input element, autocomplete attribute of object element, autocomplete attribute of output element, autocomplete attribute of select element, autocomplete attribute of textarea element ) §: Defined in HTML
address-level3 (value for autocomplete attribute of button element, autocomplete attribute of fieldset element, autocomplete attribute of input element, autocomplete attribute of object element, autocomplete attribute of output element, autocomplete attribute of select element, autocomplete attribute of textarea element ) §: Defined in HTML
address-level4 (value for autocomplete attribute of button element, autocomplete attribute of fieldset element, autocomplete attribute of input element, autocomplete attribute of object element, autocomplete attribute of output element, autocomplete attribute of select element, autocomplete attribute of textarea element ) §: Defined in HTML
address-line1 (value for autocomplete attribute of button element, autocomplete attribute of fieldset element, autocomplete attribute of input element, autocomplete attribute of object element, autocomplete attribute of output element, autocomplete attribute of select element, autocomplete attribute of textarea element ) §: Defined in HTML
address-line2 (value for autocomplete attribute of button element, autocomplete attribute of fieldset element, autocomplete attribute of input element, autocomplete attribute of object element, autocomplete attribute of output element, autocomplete attribute of select element, autocomplete attribute of textarea element ) §: Defined in HTML
address-line3 (value for autocomplete attribute of button element, autocomplete attribute of fieldset element, autocomplete attribute of input element, autocomplete attribute of object element, autocomplete attribute of output element, autocomplete attribute of select element, autocomplete attribute of textarea element ) §: Defined in HTML
addressable character (concept) §: Defined in SVG 2
AddressErrors (WebIDL dictionary) §: Defined in Payment Request API; Related terms: AddressErrors.addressLine, AddressErrors.city, AddressErrors.country, AddressErrors.dependentLocality, AddressErrors.organization, AddressErrors.phone, AddressErrors.postalCode, AddressErrors.recipient, AddressErrors.region, AddressErrors.sortingCode; see also WebIDLPedia
AddressErrors.addressLine (WebIDL dictionary member) §: Defined in Payment Request API
ContactAddress.addressLine (WebIDL attribute) §: Defined in Contact Picker API
GPUSamplerDescriptor.addressModeU (WebIDL dictionary member) §: Defined in WebGPU
GPUSamplerDescriptor.addressModeV (WebIDL dictionary member) §: Defined in WebGPU
GPUSamplerDescriptor.addressModeW (WebIDL dictionary member) §: Defined in WebGPU
AddRestrictedFunctionProperties (algorithm) §: Defined in ECMAScript
InstallEvent.addRoutes(rules) (WebIDL operation) §: Defined in Service Workers
CSSStyleSheet.addRule(selector, style, index) (WebIDL operation) §: Defined in CSSOM
External.AddSearchProvider() (WebIDL operation) §: Defined in HTML
addsourcebuffer (event) §: Defined in Media Source Extensions™
MediaSource.addSourceBuffer() (WebIDL operation) §: Defined in Media Source Extensions™
HandwritingDrawing.addStroke(stroke) (WebIDL operation) §: Defined in Handwriting Recognition API
Subscriber.addTeardown(teardown) (WebIDL operation) §: Defined in Observable
HTMLMediaElement.addTextTrack(kind, label, language) (WebIDL operation) §: Defined in HTML; Referenced in Open Screen Protocol
AddToKeptObjects (algorithm) §: Defined in ECMAScript
addtrack (event for AudioTrackList, TextTrackList interface, VideoTrackList interface ) §: Defined in HTML; Referenced in Media Source Extensions™
addtrack (event) §: Defined in Media Capture and Streams; Referenced in Media Capture from DOM Elements
MediaStream.addTrack() (WebIDL operation) §: Defined in Media Capture and Streams
RTCPeerConnection.addTrack() (WebIDL operation) §: Defined in WebRTC 1.0
addTransceiver sendEncodings validation steps (concept for RTCPeerConnection ) §: Defined in WebRTC 1.0
RTCPeerConnection.addTransceiver() (WebIDL operation) §: Defined in WebRTC 1.0
AddValueToKeyedGroup (algorithm) §: Defined in ECMAScript
AddWaiter (algorithm) §: Defined in ECMAScript
adjoining margins (concept) §: Defined in CSS 2.1; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
adopt (concept) §: Defined in DOM; Referenced in HTML
Adopted Draft (concept) §: Defined in W3C Process Document
DocumentOrShadowRoot.adoptedStyleSheets (WebIDL attribute) §: Defined in CSSOM
adopting steps (concept) §: Defined in DOM; Referenced in HTML, Portals
Document.adoptNode(node) (WebIDL operation) §: Defined in DOM
PortalActivateEvent.adoptPredecessor() (WebIDL operation) §: Defined in Portals
AdRender (WebIDL dictionary) §: Defined in Protected Audience; Related terms: AdRender.height, AdRender.url, AdRender.width; see also WebIDLPedia
AuctionAd.adRenderId (WebIDL dictionary member) §: Defined in Protected Audience
GenerateBidInterestGroup.ads (WebIDL dictionary member) §: Defined in Protected Audience
GenerateBidInterestGroup.adSizes (WebIDL dictionary member) §: Defined in Protected Audience
"adts" (value for AacBitstreamFormat WebIDL enumeration) §: Defined in AAC WebCodecs Registration
advance measure (concept for <length> ) §: Defined in CSS Values 3 , CSS Values 4; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
IDBCursor.advance(count) (WebIDL operation) §: Defined in Indexed DB 3.0
Constraints.advanced (WebIDL dictionary member) §: Defined in Media Capture and Streams
MediaTrackConstraints.advanced (WebIDL dictionary member) §: Defined in Media Capture and Streams
FontMetrics.advances (WebIDL attribute) §: Defined in Font Metrics API 1
AdvanceStringIndex (algorithm) §: Defined in ECMAScript
advertisementreceived (event for BluetoothDeviceEventHandlers ) §: Defined in Web Bluetooth; Referenced in Web Bluetooth Scanning
Advisory Board (concept) §: Defined in W3C Process Document
Advisory Committee (concept) §: Defined in W3C Process Document
Advisory Committee Appeal (concept) §: Defined in W3C Process Document
Advisory Committee representative (concept) §: Defined in W3C Process Document
Advisory Committee review (concept) §: Defined in W3C Process Document
AesCbcParams (WebIDL dictionary) §: Defined in Web Cryptography API; Related terms: AesCbcParams.iv; see also WebIDLPedia
AesCtrParams (WebIDL dictionary) §: Defined in Web Cryptography API; Related terms: AesCtrParams.counter, AesCtrParams.length; see also WebIDLPedia
AesDerivedKeyParams (WebIDL dictionary) §: Defined in Web Cryptography API; Related terms: AesDerivedKeyParams.length; see also WebIDLPedia
AesGcmParams (WebIDL dictionary) §: Defined in Web Cryptography API; Related terms: AesGcmParams.additionalData, AesGcmParams.iv, AesGcmParams.tagLength; see also WebIDLPedia
AesKeyAlgorithm (WebIDL dictionary) §: Defined in Web Cryptography API; Related terms: AesKeyAlgorithm.length; see also WebIDLPedia
AesKeyGenParams (WebIDL dictionary) §: Defined in Web Cryptography API; Related terms: AesKeyGenParams.length; see also WebIDLPedia
::after (CSS selector) §: Defined in CSS Pseudo-Elements 4 , CSS 2.2 , Selectors 3; Referenced in CSS Display 4, CSS Snapshot 2022, CSS Snapshot 2023, CSS Cascading 3, CSS Cascading 4, CSS Cascading 5, CSS Conditional 5, CSS Containment 1, CSS Containment 2, CSS Generated Content 3, CSS Layout API 1, CSS Lists 3, CSS Nesting, CSS Paged Media 3, CSS Pseudo-Elements 4, CSS Scroll Snap 1, CSS Speech 1, CSS User Interface 4, CSSOM, Selectors 4, WebVTT: The Web Video Text Tracks Format
:after (concept) §: Defined in CSS 2.1; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
after (concept for boundary point ) §: Defined in DOM; Referenced in execCommand, URL Fragment Text Directives, Selection API
after (CSS value for scroll-marker-group ) §: Defined in CSS Overflow 5
after (CSS value for content() ) §: Defined in CSS Generated Content 3
after phase (concept for animation effect ) §: Defined in Web Animations; Referenced in CSS Animations 2, Web Animations 2
after-change style (concept) §: Defined in CSS Transitions; Referenced in CSS Snapshot 2022, CSS Snapshot 2023, CSS Transitions 2, Web Animations
"after-transition" (value for NavigationFocusReset WebIDL enumeration) §: Defined in HTML
"after-transition" (value for NavigationScrollBehavior WebIDL enumeration) §: Defined in HTML
AnimationEffect.after(...effects) (WebIDL operation) §: Defined in Web Animations 2
ChildNode.after(...nodes) (WebIDL operation) §: Defined in DOM
afterprint (event for Window ) §: Defined in HTML
<age> (CSS type for voice-family ) §: Defined in CSS Speech 1
agent (concept for realm ) §: Defined in HTML; Referenced in WebAssembly JavaScript Interface: Exception Handling, Prioritized Task Scheduling, Protected Audience
agent (concept for ECMAScript ) §: Defined in ECMAScript; Referenced in ECMAScript Internationalization API, Time Zone Canonicalization, Temporal, WebAssembly JavaScript Interface: ESM Integration, WebAssembly JavaScript Interface: Promise Integration, WebAssembly JavaScript Interface: JS String Builtins, Protected Audience, Compute Pressure 1, Media Source Extensions™, WebAssembly JavaScript Interface, WebGPU
agent cluster (concept for ECMAScript ) §: Defined in ECMAScript; Referenced in HTML, WebAssembly JavaScript Interface: ESM Integration, WebAssembly JavaScript Interface: Exception Handling, WebAssembly JavaScript Interface: Promise Integration, WebAssembly JavaScript Interface: JS String Builtins, Web IDL, Measure Memory API, Protected Audience, Media Source Extensions™, WebAssembly JavaScript Interface, WebGPU
Agent Events Record (concept for ECMAScript ) §: Defined in ECMAScript
Agent Record (concept for ECMAScript ) §: Defined in ECMAScript
agent signifier (concept for ECMAScript ) §: Defined in ECMAScript; Referenced in HTML, Measure Memory API
agent-order slice (concept for ECMAScript ) §: Defined in ECMAScript
AgentCanSuspend (algorithm) §: Defined in ECMAScript
AgentSignifier (algorithm) §: Defined in ECMAScript
AggregateError (exception) §: Defined in ECMAScript; Related terms: AggregateError.message, AggregateError.name, new AggregateError(errors, message, options)
%AggregateError.prototype% (WebIDL interface) §: Defined in ECMAScript; Referenced in ECMAScript Async Explicit Resource Management, ECMAScript Explicit Resource Management; see also WebIDLPedia
new AggregateError(errors, message, options) (WebIDL constructor) §: Defined in ECMAScript
%AggregateError% (exception) §: Defined in ECMAScript; Referenced in ECMAScript Async Explicit Resource Management, ECMAScript Explicit Resource Management, Source Phase Imports
ProtectedAudiencePrivateAggregationConfig.aggregationCoordinatorOrigin (WebIDL dictionary member) §: Defined in Private Aggregation API
SharedStoragePrivateAggregationConfig.aggregationCoordinatorOrigin (WebIDL dictionary member) §
SharedStoragePrivateAggregationConfig.aggregationCoordinatorOrigin (WebIDL dictionary member) §: Defined in Private Aggregation API , Shared Storage API
MediaMetadata.album (WebIDL attribute) §: Defined in Media Session
MediaMetadataInit.album (WebIDL dictionary member) §: Defined in Media Session
Window.alert() (WebIDL operation) §: Defined in HTML
Window.alert(message) (WebIDL operation) §: Defined in HTML; Referenced in WebDriver BiDi, WebDriver
JsonWebKey.alg (WebIDL dictionary member) §: Defined in Web Cryptography API
PublicKeyCredentialParameters.alg (WebIDL dictionary member) §: Defined in Web Authentication
Algorithm (WebIDL dictionary) §: Defined in Web Cryptography API; Related terms: Algorithm.name; see also WebIDLPedia
CryptoKey.algorithm (WebIDL attribute) §: Defined in Web Cryptography API
RTCDtlsFingerprint.algorithm (WebIDL dictionary member) §: Defined in WebRTC 1.0
WebTransportHash.algorithm (WebIDL dictionary member) §: Defined in WebTransport
algorithm for determining the form of an embellished operator (algorithm) §: Defined in MathML Core
algorithm for determining the properties of an embellished operator (algorithm) §: Defined in MathML Core
algorithm for stretching operators along the block axis (algorithm) §: Defined in MathML Core
algorithm for stretching operators along the inline axis (algorithm) §: Defined in MathML Core
algorithm to determine the category of an operator (algorithm) §: Defined in MathML Core
algorithm to set the properties of an operator from its category (algorithm) §: Defined in MathML Core
AlgorithmIdentifier (WebIDL type alias) §: Defined in Web Cryptography API; see also WebIDLPedia
alias (CSS value for cursor ) §: Defined in CSS User Interface 3 , CSS User Interface 4; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
aliceblue (concept) §: Defined in CSS Color 3; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
aliceblue (CSS value for <color>, <named-color> type ) §: Defined in CSS Color 4
align (markup attribute for caption ) §: Defined in HTML
align (markup attribute for col ) §: Defined in HTML
align (markup attribute for div ) §: Defined in HTML
align (markup attribute for embed ) §: Defined in HTML
align (markup attribute for hr ) §: Defined in HTML
align (markup attribute for h1, h2 element, h3 element, h4 element, h5 element, h6 element ) §: Defined in HTML
align (markup attribute for iframe ) §: Defined in HTML
align (markup attribute for input ) §: Defined in HTML
align (markup attribute for img ) §: Defined in HTML
align (markup attribute for legend ) §: Defined in HTML
align (markup attribute for object ) §: Defined in HTML
align (markup attribute for p ) §: Defined in HTML
align (markup attribute for table ) §: Defined in HTML
align (markup attribute for tbody ) §: Defined in HTML
align (markup attribute for td, th element ) §: Defined in HTML
align (markup attribute for tr ) §: Defined in HTML
HTMLDivElement.align (WebIDL attribute) §: Defined in HTML
HTMLEmbedElement.align (WebIDL attribute) §: Defined in HTML
HTMLHeadingElement.align (WebIDL attribute) §: Defined in HTML
HTMLHRElement.align (WebIDL attribute) §: Defined in HTML
HTMLIFrameElement.align (WebIDL attribute) §: Defined in HTML
HTMLImageElement.align (WebIDL attribute) §: Defined in HTML
HTMLInputElement.align (WebIDL attribute) §: Defined in HTML
HTMLLegendElement.align (WebIDL attribute) §: Defined in HTML
HTMLObjectElement.align (WebIDL attribute) §: Defined in HTML
HTMLParagraphElement.align (WebIDL attribute) §: Defined in HTML
HTMLTableCaptionElement.align (WebIDL attribute) §: Defined in HTML
HTMLTableCellElement.align (WebIDL attribute) §: Defined in HTML
HTMLTableColElement.align (WebIDL attribute) §: Defined in HTML
HTMLTableElement.align (WebIDL attribute) §: Defined in HTML
HTMLTableRowElement.align (WebIDL attribute) §: Defined in HTML
HTMLTableSectionElement.align (WebIDL attribute) §: Defined in HTML
SVGPreserveAspectRatio.align (WebIDL attribute) §: Defined in SVG 2
VTTCue.align (WebIDL attribute) §: Defined in WebVTT: The Web Video Text Tracks Format
align-content (CSS property) §: Defined in CSS Box Alignment 3 , CSS Flexbox 1; Referenced in Compatibility, CSS Display 4, CSS Grid Layout 3, CSS Snapshot 2022, CSS Snapshot 2022, CSS Snapshot 2023, CSS Snapshot 2023, CSS Grid Layout 1, CSS Grid Layout 2, CSS Inline Layout 3, CSS Overflow 3, CSS Typed OM 1; Related terms: CSS value baseline, CSS value center, CSS value center, CSS value end, CSS value first baseline, CSS value flex-end, CSS value flex-end, CSS value flex-start, CSS value flex-start, CSS value last baseline, CSS value normal, CSS value space-around, CSS value space-around, CSS value space-between, CSS value space-between, CSS value space-evenly, CSS value start, CSS value stretch, CSS value stretch
align-items (CSS property) §: Defined in CSS Box Alignment 3 , CSS Flexbox 1; Referenced in Compatibility, CSS Snapshot 2022, CSS Snapshot 2022, CSS Snapshot 2023, CSS Snapshot 2023, CSS Anchor Positioning, CSS Grid Layout 1, CSS Grid Layout 2, CSS Typed OM 1; Related terms: CSS value anchor-center, CSS value auto, CSS value baseline, CSS value baseline, CSS value center, CSS value first baseline, CSS value flex-end, CSS value flex-start, CSS value last baseline, CSS value stretch
align-self (CSS property) §: Defined in CSS Box Alignment 3 , CSS Flexbox 1; Referenced in Compatibility, CSS Snapshot 2022, CSS Snapshot 2022, CSS Snapshot 2023, CSS Snapshot 2023, CSS Anchor Positioning, CSS Grid Layout 1, CSS Grid Layout 2, CSS Rhythmic Sizing, CSS Typed OM 1; Related terms: CSS value anchor-center, CSS value auto, CSS value auto, CSS value baseline, CSS value baseline, CSS value center, CSS value center, CSS value end, CSS value first baseline, CSS value flex-end, CSS value flex-end, CSS value flex-start, CSS value flex-start, CSS value last baseline, CSS value normal, CSS value self-end, CSS value self-start, CSS value start, CSS value stretch, CSS value stretch
CSSPositionTryDescriptors.align-self (WebIDL attribute) §: Defined in CSS Anchor Positioning
alignment baseline (concept) §: Defined in CSS Box Alignment 3; Referenced in CSS Grid Layout 3, CSS Snapshot 2022, CSS Snapshot 2023, CSS Flexbox 1, CSS Grid Layout 1, CSS Grid Layout 2
alignment baseline (concept) §: Defined in CSS Inline Layout 3
alignment baseline (concept) §: Defined in SVG 2
alignment character (CSS value for text-align ) §: Defined in CSS Text 4
alignment container (concept) §: Defined in CSS Box Alignment 3; Referenced in CSS Snapshot 2022, CSS Snapshot 2023, CSS Positioned Layout 3, CSS Scroll Snap 1, CSS Sizing 4
alignment subject (concept) §: Defined in CSS Box Alignment 3; Referenced in CSS Grid Layout 3, CSS Snapshot 2022, CSS Snapshot 2023, CSS Scroll Snap 1
alignment-baseline (CSS property) §: Defined in CSS Inline Layout 3; Referenced in CSS Box Alignment 3, CSS Typed OM 1; Related terms: CSS value alphabetic, CSS value baseline, CSS value central, CSS value ideographic, CSS value mathematical, CSS value middle, CSS value text-after-edge, CSS value text-before-edge, CSS value text-bottom, CSS value text-top
CSSPositionTryDescriptors.alignSelf (WebIDL attribute) §: Defined in CSS Anchor Positioning
AlignSetting (WebIDL enumeration) §: Defined in WebVTT: The Web Video Text Tracks Format; Related terms: value center, value end, value left, value right, value start; see also WebIDLPedia
alink (markup attribute for body ) §: Defined in HTML
HTMLBodyElement.aLink (WebIDL attribute) §: Defined in HTML
Document.alinkColor (WebIDL attribute) §: Defined in HTML
all (CSS value for border-limit ) §: Defined in CSS Borders and Box Decorations 4
all (CSS value for column-span ) §: Defined in CSS Multicol 2 , CSS Multicol 1; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
"all" (value for SameSiteCookiesType WebIDL enumeration) §: Defined in Extending Storage Access API to non-cookie storage
all (CSS value for anchor-scope ) §: Defined in CSS Anchor Positioning
all (CSS value for break-after, break-before property ) §: Defined in CSS Fragmentation 4
all (CSS property) §: Defined in CSS Cascading 3 , CSS Cascading 4 , CSS Cascading 5; Referenced in CSS Variables 2, CSS Snapshot 2022, CSS Snapshot 2023, CSS Cascading 6, CSS Logical Properties 1, CSS Spatial Navigation 1, CSS Transitions, CSS Typed OM 1, CSS User Interface 4, CSS Variables 1; Related terms: CSS value inherit, CSS value initial, CSS value revert, CSS value revert-layer, CSS value unset
all (CSS value for initial-letter-wrap ) §: Defined in CSS Inline Layout 3
"all" (value for FocusableAreaSearchMode WebIDL enumeration) §: Defined in CSS Spatial Navigation 1
all (CSS value for clear ) §: Defined in CSS Page Floats
all (CSS value for text-decoration-skip-box ) §: Defined in CSS Text Decoration 4
all (CSS value for text-decoration-skip-spaces ) §: Defined in CSS Text Decoration 4
all (CSS value for text-decoration-skip-ink ) §: Defined in CSS Text Decoration 4
all (CSS value for transition-property ) §: Defined in CSS Transitions; Referenced in CSS Snapshot 2022, CSS Snapshot 2023, CSS Transitions 2
all (CSS value for user-select ) §: Defined in CSS User Interface 4
all (CSS value for text-combine-upright ) §: Defined in CSS Writing Modes 3 , CSS Writing Modes 4; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
all (CSS value for @media ) §: Defined in CSS 2.2 , Media Queries 4 , Media Queries 5; Referenced in CSS Snapshot 2022, CSS Snapshot 2023, CSS Cascading 4
all (CSS value for timeline-scope ) §: Defined in Scroll-driven Animations
"all" (value for ServiceWorkerUpdateViaCache WebIDL enumeration) §: Defined in Service Workers
"all" (value for ClientType WebIDL enumeration) §: Defined in Service Workers
"all" (value for GPUTextureAspect WebIDL enumeration) §: Defined in WebGPU
"all" (value for RTCIceTransportPolicy WebIDL enumeration) §: Defined in WebRTC 1.0
Document.all (WebIDL attribute) §: Defined in HTML; Referenced in ECMAScript
StorageAccessTypes.all (WebIDL dictionary member) §: Defined in Extending Storage Access API to non-cookie storage
GPUColorWrite.ALL (WebIDL constant) §: Defined in WebGPU
"all-petite-caps" (value for CanvasFontVariantCaps WebIDL enumeration) §: Defined in HTML
all-petite-caps (CSS value for font-variant-caps ) §: Defined in CSS Fonts 4; Referenced in CSS Snapshot 2023
all-scroll (CSS value for cursor ) §: Defined in CSS User Interface 3 , CSS User Interface 4; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
"all-small-caps" (value for CanvasFontVariantCaps WebIDL enumeration) §: Defined in HTML
all-small-caps (CSS value for font-variant-caps ) §: Defined in CSS Fonts 4; Referenced in CSS Snapshot 2023
'all' media group (concept) §: Defined in CSS 2.1; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
Promise.all(iterable) (WebIDL operation) §: Defined in ECMAScript; Referenced in Web IDL
AllAcceptedCredentialsOptions.allAcceptedCredentialIds (WebIDL dictionary member) §: Defined in Web Authentication
AllAcceptedCredentialsOptions (WebIDL dictionary) §: Defined in Web Authentication; Related terms: AllAcceptedCredentialsOptions.allAcceptedCredentialIds, AllAcceptedCredentialsOptions.rpId, AllAcceptedCredentialsOptions.userId; see also WebIDLPedia
AllCharacters (algorithm) §: Defined in ECMAScript
AllocateArrayBuffer (algorithm) §: Defined in ECMAScript; Referenced in Web IDL
AllocateSharedArrayBuffer (algorithm) §: Defined in ECMAScript; Referenced in Web IDL
AllocateTypedArray (algorithm) §: Defined in ECMAScript; Referenced in Uint8Array to/from base64
AllocateTypedArrayBuffer (algorithm) §: Defined in ECMAScript
AudioData.allocationSize(options) (WebIDL operation) §: Defined in WebCodecs
VideoFrame.allocationSize(options) (WebIDL operation) §: Defined in WebCodecs
'allow' (grammar) §: Defined in Content Security Policy 3
allow (markup attribute for iframe ) §: Defined in HTML; Referenced in Fullscreen API, Fenced Frame, WebOTP API, Generic Sensor API, Geolocation, HTML Accessibility API Mappings 1.0, Payment Request API, Permissions Policy, Permissions, Web Share API, Web Authentication
allow (markup attribute for fencedframe ) §: Defined in Fenced Frame
HTMLFencedFrameElement.allow (WebIDL attribute) §: Defined in Fenced Frame
HTMLIFrameElement.allow (WebIDL attribute) §: Defined in HTML; Referenced in Capability Delegation
allow declarative shadow roots (concept for Document ) §: Defined in DOM; Referenced in HTML Sanitizer API
Allow-Cross-Origin-Event-Reporting: (HTTP header) §: Defined in Fenced Frame
Allow-CSP-From: (HTTP header) §: Defined in Content Security Policy: Embedded Enforcement
allow-downloads (value for sandbox attribute of iframe element ) §: Defined in HTML; Referenced in Fenced Frame
allow-end (CSS value for hanging-punctuation ) §: Defined in CSS Text 3 , CSS Text 4; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
Allow-Fenced-Frame-Automatic-Beacons: (HTTP header) §: Defined in Fenced Frame
allow-forms (value for sandbox attribute of iframe element ) §: Defined in HTML; Referenced in Fenced Frame
allow-keywords (CSS value for interpolate-size ) §: Defined in CSS Values 5
allow-modals (value for sandbox attribute of iframe element ) §: Defined in HTML; Referenced in Fenced Frame
allow-orientation-lock (value for sandbox attribute of iframe element ) §: Defined in HTML; Referenced in Fenced Frame
allow-pointer-lock (value for sandbox attribute of iframe element ) §: Defined in HTML; Referenced in Fenced Frame
allow-popups (value for sandbox attribute of iframe element ) §: Defined in HTML; Referenced in Fenced Frame
allow-popups-to-escape-sandbox (value for sandbox attribute of iframe element ) §: Defined in HTML; Referenced in Fenced Frame
allow-presentation (value for sandbox attribute of iframe element ) §: Defined in HTML; Referenced in Fenced Frame
allow-same-origin (value for sandbox attribute of iframe element ) §: Defined in HTML; Referenced in Fenced Frame
allow-scripts (value for sandbox attribute of iframe element ) §: Defined in HTML; Referenced in Fenced Frame
allow-storage-access-by-user-activation (value for sandbox attribute of iframe element ) §: Defined in The Storage Access API
allow-top-navigation (value for sandbox attribute of iframe element ) §: Defined in HTML; Referenced in Fenced Frame
allow-top-navigation-by-user-activation (value for sandbox attribute of iframe element ) §: Defined in HTML; Referenced in Fenced Frame
allow-top-navigation-to-custom-protocols (value for sandbox attribute of iframe element ) §: Defined in HTML; Referenced in Fenced Frame
GenerateBidOutput.allowComponentAuction (WebIDL dictionary member) §: Defined in Protected Audience
ScoreAdOutput.allowComponentAuction (WebIDL dictionary member) §: Defined in Protected Audience
PublicKeyCredentialRequestOptions.allowCredentials (WebIDL dictionary member) §: Defined in Web Authentication; Referenced in Secure Payment Confirmation
PublicKeyCredentialRequestOptionsJSON.allowCredentials (WebIDL dictionary member) §: Defined in Web Authentication
"allowed" (value for AutoplayPolicy WebIDL enumeration) §: Defined in Autoplay Policy Detection
allowed reporting origins (concept for fenced frame reporting metadata ) §: Defined in Fenced Frame; Referenced in Protected Audience
allowed required constraints for device selection (concept) §: Defined in Media Capture and Streams
Allowed signed exchange link info (concept) §: Defined in Loading Signed Exchanges
allowed to modify the clipboard (concept) §: Defined in Clipboard API and events
allowed to use (concept) §: Defined in HTML; Referenced in Fullscreen API, Private Aggregation API, Topics API, The Storage Access API, Web Bluetooth, Web Bluetooth Scanning, Attribution Reporting, Capability Delegation, Digital Goods API, Direct Sockets API, Fenced Frame, Idle Detection API, Keyboard Map, Local Font Access, Prerendering Revamped, Page Lifecycle, Web Serial API, Shared Storage API, Protected Audience, WebOTP API, Web Smart Card API, WebHID API, WebUSB API, Audio Output Devices API, Battery Status API, Compute Pressure 1, Credential Management 1, Encrypted Media Extensions, Federated Credential Management API, Gamepad, Generic Sensor API, Geolocation, Media Capture and Streams, Viewport Capture, Device Orientation and Motion, Payment Request API, Permissions, Picture-in-Picture, Screen Capture, Screen Wake Lock API, Web Share API, Web Authentication, Web MIDI API, Web Neural Network API, Window Management
allowed-alt-sxg (value for rel attribute of link element ) §: Defined in Loading Signed Exchanges
"allowed-muted" (value for AutoplayPolicy WebIDL enumeration) §: Defined in Autoplay Policy Detection
AllowedBluetoothDevice (WebIDL dictionary) §: Defined in Web Bluetooth; Related terms: AllowedBluetoothDevice.[[device]], AllowedBluetoothDevice.allowedManufacturerData, AllowedBluetoothDevice.allowedServices, AllowedBluetoothDevice.deviceId, AllowedBluetoothDevice.mayUseGATT; see also WebIDLPedia
SerialPortRequestOptions.allowedBluetoothServiceClassIds (WebIDL dictionary member) §: Defined in Web Serial API
BluetoothPermissionStorage.allowedDevices (WebIDL dictionary member) §: Defined in Web Bluetooth
USBPermissionStorage.allowedDevices (WebIDL dictionary member) §: Defined in WebUSB API
PermissionsPolicy.allowedFeatures() (WebIDL operation) §: Defined in Permissions Policy
BluetoothDevice.[[allowedManufacturerData]] (internal slot) §: Defined in Web Bluetooth
AllowedBluetoothDevice.allowedManufacturerData (WebIDL dictionary member) §: Defined in Web Bluetooth
AuctionAd.allowedReportingOrigins (WebIDL dictionary member) §: Defined in Protected Audience
BluetoothDevice.[[allowedServices]] (internal slot) §: Defined in Web Bluetooth
AllowedBluetoothDevice.allowedServices (WebIDL dictionary member) §: Defined in Web Bluetooth
AllowedUSBDevice (WebIDL dictionary) §: Defined in WebUSB API; Related terms: AllowedUSBDevice.[[devices]], AllowedUSBDevice.productId, AllowedUSBDevice.serialNumber, AllowedUSBDevice.vendorId; see also WebIDLPedia
allowfullscreen (markup attribute for iframe ) §: Defined in HTML; Referenced in Fullscreen API, HTML Accessibility API Mappings 1.0, Permissions Policy
HTMLIFrameElement.allowFullscreen (WebIDL attribute) §: Defined in HTML
allowlist (concept) §: Defined in Permissions Policy; Referenced in Fenced Frame
WebTransportOptions.allowPooling (WebIDL dictionary member) §: Defined in WebTransport
AllowResizable (WebIDL extended attribute) §: Defined in Web IDL
allows all inline behavior (concept for source list ) §: Defined in Content Security Policy 3; Referenced in Content Security Policy: Embedded Enforcement
PermissionsPolicy.allowsFeature(feature, origin) (WebIDL operation) §: Defined in Permissions Policy
AllowShared (WebIDL extended attribute) §: Defined in Web IDL; Referenced in Encoding
AllowSharedBufferSource (WebIDL type alias) §: Defined in Web IDL; Referenced in Encoding, File System, WebCodecs, WebGPU; see also WebIDLPedia
allowtransparency (markup attribute for iframe ) §: Defined in HTML
ClipboardPermissionDescriptor.allowWithoutGesture (WebIDL dictionary member) §: Defined in Clipboard API and events
"allpass" (value for BiquadFilterType WebIDL enumeration) §: Defined in Web Audio API
Promise.allSettled(iterable) (WebIDL operation) §: Defined in ECMAScript
AuctionAdConfig.allSlotsRequestedSizes (WebIDL dictionary member) §: Defined in Protected Audience
alpha (CSS value for rgb() ) §: Defined in CSS Color 5
alpha (CSS value for hsl() ) §: Defined in CSS Color 5
alpha (CSS value for hwb() ) §: Defined in CSS Color 5
alpha (CSS value for lab() ) §: Defined in CSS Color 5
alpha (CSS value for oklab() ) §: Defined in CSS Color 5
alpha (CSS value for lch() ) §: Defined in CSS Color 5
alpha (CSS value for oklch() ) §: Defined in CSS Color 5
alpha (CSS value for color() ) §: Defined in CSS Color 5
alpha (CSS value for mask-mode ) §: Defined in CSS Masking 1; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
alpha (CSS value for mask-border-mode ) §: Defined in CSS Masking 1; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
alpha (CSS value for mask-type ) §: Defined in CSS Masking 1; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
CanvasRenderingContext2DSettings.alpha (WebIDL dictionary member) §: Defined in HTML
CSSColor.alpha (WebIDL attribute) §: Defined in CSS Typed OM 1
CSSHSL.alpha (WebIDL attribute) §: Defined in CSS Typed OM 1
CSSHWB.alpha (WebIDL attribute) §: Defined in CSS Typed OM 1
CSSLab.alpha (WebIDL attribute) §: Defined in CSS Typed OM 1
CSSLCH.alpha (WebIDL attribute) §: Defined in CSS Typed OM 1
CSSOKLab.alpha (WebIDL attribute) §: Defined in CSS Typed OM 1
CSSOKLCH.alpha (WebIDL attribute) §: Defined in CSS Typed OM 1
CSSRGB.alpha (WebIDL attribute) §: Defined in CSS Typed OM 1
DeviceMotionEventRotationRate.alpha (WebIDL attribute) §: Defined in Device Orientation and Motion
DeviceMotionEventRotationRateInit.alpha (WebIDL dictionary member) §: Defined in Device Orientation and Motion
DeviceOrientationEvent.alpha (WebIDL attribute) §: Defined in Device Orientation and Motion
DeviceOrientationEventInit.alpha (WebIDL dictionary member) §: Defined in Device Orientation and Motion
GPUBlendState.alpha (WebIDL dictionary member) §: Defined in WebGPU
ImageBitmapRenderingContextSettings.alpha (WebIDL dictionary member) §: Defined in HTML
MLEluOptions.alpha (WebIDL dictionary member) §: Defined in Web Neural Network API
MLGemmOptions.alpha (WebIDL dictionary member) §: Defined in Web Neural Network API
MLHardSigmoidOptions.alpha (WebIDL dictionary member) §: Defined in Web Neural Network API
MLLeakyReluOptions.alpha (WebIDL dictionary member) §: Defined in Web Neural Network API
MLLinearOptions.alpha (WebIDL dictionary member) §: Defined in Web Neural Network API
PaintRenderingContext2DSettings.alpha (WebIDL dictionary member) §: Defined in CSS Painting API 1
VideoEncoderConfig.alpha (WebIDL dictionary member) §: Defined in WebCodecs
VideoFrameInit.alpha (WebIDL dictionary member) §: Defined in WebCodecs
XRWebGLLayerInit.alpha (WebIDL dictionary member) §: Defined in WebXR Device API
GPUColorWrite.ALPHA (WebIDL constant) §: Defined in WebGPU
alpha channel (concept) §: Defined in CSS Color 4
"alpha-blend" (value for XREnvironmentBlendMode WebIDL enumeration) §: Defined in WebXR Augmented Reality 1
<alpha-value> (CSS type for <color> ) §: Defined in CSS Color 4; Referenced in CSS Color HDR 1, CSS Color 5, CSSOM
Alphabet (concept) §: Defined in Internationalization Glossary
"alphabetic" (value for CanvasTextBaseline WebIDL enumeration) §: Defined in HTML
alphabetic (CSS value for system descriptor of @counter-style @rule ) §: Defined in CSS Counter Styles 3; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
alphabetic (CSS value for dominant-baseline ) §: Defined in CSS Inline Layout 3
alphabetic (CSS value for alignment-baseline, vertical-align property ) §: Defined in CSS Inline Layout 3
alphabetic (CSS value for <<text-edge>>, line-fit-edge property ) §: Defined in CSS Inline Layout 3
alphabetic (CSS value for initial-letter-align ) §: Defined in CSS Inline Layout 3
alphabetic baseline (concept) §: Defined in CSS Inline Layout 3
TextMetrics.alphabeticBaseline (WebIDL attribute) §: Defined in HTML
GPUCanvasConfiguration.alphaMode (WebIDL dictionary member) §: Defined in WebGPU
AlphaOption (WebIDL enumeration) §: Defined in WebCodecs; Related terms: value discard, value keep; see also WebIDLPedia
EncodedVideoChunkMetadata.alphaSideData (WebIDL dictionary member) §: Defined in WebCodecs
GPUMultisampleState.alphaToCoverageEnabled (WebIDL dictionary member) §: Defined in WebGPU
<alphavalue> (concept) §: Defined in CSS Color 3; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
ALPN negotiated protocol (concept for connection timing info ) §: Defined in Fetch; Referenced in WebDriver BiDi, Resource Timing
alt (markup attribute for img ) §: Defined in HTML; Referenced in HTML Accessibility API Mappings 1.0, ARIA in HTML
alt (markup attribute for area ) §: Defined in HTML; Referenced in HTML Accessibility API Mappings 1.0
alt (markup attribute for input ) §: Defined in HTML; Referenced in HTML Accessibility API Mappings 1.0
HTMLAreaElement.alt (WebIDL attribute) §: Defined in HTML
HTMLImageElement.alt (WebIDL attribute) §: Defined in HTML
HTMLInputElement.alt (WebIDL attribute) §: Defined in HTML
alternate (value for rel attribute of a, rel attribute of area element, rel attribute of link element ) §: Defined in HTML; Referenced in Loading Signed Exchanges
alternate (CSS value for animation-direction ) §: Defined in CSS Animations 1; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
alternate (CSS value for ruby-position ) §: Defined in CSS Ruby Annotation Layout 1; Referenced in HTML Ruby Markup Extensions
"alternate" (value for PlaybackDirection WebIDL enumeration) §: Defined in Web Animations
USBInterface.alternate (WebIDL attribute) §: Defined in WebUSB API
alternate AC representative (concept) §: Defined in W3C Process Document
Alternate signed exchange link info (concept) §: Defined in Loading Signed Exchanges
Alternate signed exchange preload info (concept) §: Defined in Loading Signed Exchanges
alternate-reverse (CSS value for animation-direction ) §: Defined in CSS Animations 1; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
"alternate-reverse" (value for PlaybackDirection WebIDL enumeration) §: Defined in Web Animations
USBEndpoint.[[alternateInterface]] (internal slot) §: Defined in WebUSB API
USBInterface.[[alternates]] (internal slot) §
USBInterface.[[alternates]] (internal slot) §: Defined in WebUSB API , WebUSB API
USBAlternateInterface.[[alternateSetting]] (internal slot) §
USBAlternateInterface.[[alternateSetting]] (internal slot) §: Defined in WebUSB API , WebUSB API
HandwritingHints.alternatives (WebIDL dictionary member) §: Defined in Handwriting Recognition API
HandwritingHintsQueryResult.alternatives (WebIDL dictionary member) §: Defined in Handwriting Recognition API
GeolocationCoordinates.altitude (WebIDL attribute) §: Defined in Geolocation
GeolocationSensor.altitude (WebIDL attribute) §: Defined in Geolocation Sensor
GeolocationSensorReading.altitude (WebIDL dictionary member) §: Defined in Geolocation Sensor
GeolocationCoordinates.altitudeAccuracy (WebIDL attribute) §: Defined in Geolocation
GeolocationSensor.altitudeAccuracy (WebIDL attribute) §: Defined in Geolocation Sensor
GeolocationSensorReading.altitudeAccuracy (WebIDL dictionary member) §: Defined in Geolocation Sensor
PointerEvent.altitudeAngle (WebIDL attribute) §: Defined in Pointer Events
PointerEventInit.altitudeAngle (WebIDL dictionary member) §: Defined in Pointer Events
Touch.altitudeAngle (WebIDL attribute) §: Defined in Touch Events
TouchInit.altitudeAngle (WebIDL dictionary member) §: Defined in Touch Events
EventModifierInit.altKey (WebIDL dictionary member) §: Defined in UI Events
KeyboardEvent.altKey (WebIDL attribute) §: Defined in UI Events
MouseEvent.altKey (WebIDL attribute) §: Defined in UI Events
TouchEvent.altKey (WebIDL attribute) §: Defined in Touch Events
alttext (markup attribute for math ) §: Defined in MathML Core
"@always" (value for JsonLdEmbed WebIDL enumeration) §: Defined in JSON-LD 1.1 Framing
always (CSS value for position-visibility ) §: Defined in CSS Anchor Positioning
always (CSS value for break-after, break-before property ) §: Defined in CSS Fragmentation 4; Referenced in CSS Regions 1
always (CSS value for scrollbar-gutter ) §: Defined in CSS Overflow 4
always (CSS value for scroll-snap-stop ) §: Defined in CSS Scroll Snap 1; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
always (CSS value for speak ) §: Defined in CSS Speech 1; Referenced in CSS Display 4, CSS Snapshot 2022, CSS Snapshot 2023
always (CSS value for hyphenate-limit-lines ) §: Defined in CSS Text 4
always (CSS value for page-break-after, page-break-before property, page-break-inside property ) §: Defined in CSS 2.2
"always" (value for RedEyeReduction WebIDL enumeration) §: Defined in MediaStream Image Capture
"always" (value for CursorCaptureConstraint WebIDL enumeration) §: Defined in Screen Capture
"always" (value for GPUCompareFunction WebIDL enumeration) §: Defined in WebGPU
"ambient" (value for AudioSessionType WebIDL enumeration) §: Defined in Audio Session
"ambient-light-sensor" (permission name) §: Defined in Ambient Light Sensor
AmbientLightSensor (WebIDL interface) §: Defined in Ambient Light Sensor; Related terms: AmbientLightSensor.illuminance, new AmbientLightSensor(sensorOptions); see also WebIDLPedia
new AmbientLightSensor(sensorOptions) (WebIDL constructor) §: Defined in Ambient Light Sensor
ambiguous image URL (concept for CSS ) §: Defined in CSS Images 3; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
PaymentItem.amount (WebIDL dictionary member) §: Defined in Payment Request API
PaymentShippingOption.amount (WebIDL dictionary member) §: Defined in Payment Request API
amount to debit (concept for exfiltration budget metadata ) §: Defined in Fenced Frame
amount to debit reference (concept for exfiltration budget metadata reference ) §: Defined in Fenced Frame
amplitude (markup attribute for feComponentTransfer ) §: Defined in Filter Effects 1
SVGComponentTransferFunctionElement.amplitude (WebIDL attribute) §: Defined in Filter Effects 1
an iframe srcdoc document (concept) §: Defined in HTML; Referenced in Content Security Policy 3
An+B (concept) §: Defined in CSS Syntax 3; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
<an+b> (CSS type) §: Defined in CSS Syntax 3; Referenced in Selectors 4
analogous components (concept) §: Defined in CSS Color 4; Referenced in CSS Color 5
AnalyserNode (WebIDL interface) §: Defined in Web Audio API; Related terms: AnalyserNode.fftSize, AnalyserNode.frequencyBinCount, AnalyserNode.maxDecibels, AnalyserNode.minDecibels, AnalyserNode.smoothingTimeConstant, new AnalyserNode(context, options), AnalyserNode.getByteFrequencyData(array), AnalyserNode.getByteTimeDomainData(array), AnalyserNode.getFloatFrequencyData(array), AnalyserNode.getFloatTimeDomainData(array); see also WebIDLPedia
new AnalyserNode(context, options) (WebIDL constructor) §: Defined in Web Audio API
AnalyserOptions (WebIDL dictionary) §: Defined in Web Audio API; Related terms: AnalyserOptions.fftSize, AnalyserOptions.maxDecibels, AnalyserOptions.minDecibels, AnalyserOptions.smoothingTimeConstant; see also WebIDLPedia
ancestor (concept for tree ) §: Defined in DOM; Referenced in execCommand, Fenced Frame, Pointer Lock 2.0, UI Events, WebXR Device API
"ancestor" (value for ScriptWindowAttribution WebIDL enumeration) §: Defined in Long Animation Frames API
ancestor (concept) §: Defined in CSS 2.1; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
ancestor navigables (concept for Document ) §: Defined in HTML; Referenced in Fetch, Long Animation Frames API, Fenced Frame, Long Tasks API, Mixed Content
ancestor-source (grammar) §: Defined in Content Security Policy 3
ancestor-source-list (grammar) §: Defined in Content Security Policy 3
Location.ancestorOrigins (WebIDL attribute) §: Defined in HTML
WindowClient.ancestorOrigins (WebIDL attribute) §: Defined in Service Workers
anchor functions (concept) §: Defined in CSS Anchor Positioning
anchor node (concept for scroll-anchoring ) §: Defined in CSS Scroll Anchoring 1
Anchor positioning (concept) §: Defined in CSS Anchor Positioning
anchor-center (CSS value for align-items, align-self property, justify-items property, justify-self property ) §: Defined in CSS Anchor Positioning
<anchor-element> (CSS type) §: Defined in CSS Anchor Positioning
anchor-name (CSS property) §: Defined in CSS Anchor Positioning; Related terms: CSS value <dashed-ident>#, CSS value none
anchor-scope (CSS property) §: Defined in CSS Anchor Positioning; Related terms: CSS value all, CSS value none
<anchor-side> (CSS type) §: Defined in CSS Anchor Positioning
<anchor-size> (CSS type) §: Defined in CSS Anchor Positioning
anchor-size() (CSS function) §: Defined in CSS Anchor Positioning; Related terms: CSS value block, CSS value height, CSS value inline, CSS value self-block, CSS value self-inline, CSS value width
anchor() (CSS function) §: Defined in CSS Anchor Positioning; Related terms: CSS value bottom, CSS value center, CSS value end, CSS value inside, CSS value left, CSS value outside, CSS value right, CSS value self-end, CSS value self-start, CSS value start, CSS value top
String.anchor(name) (WebIDL operation) §: Defined in ECMAScript
Selection.anchorNode (WebIDL attribute) §: Defined in Selection API
Selection.anchorOffset (WebIDL attribute) §: Defined in Selection API
Document.anchors (WebIDL attribute) §: Defined in HTML
anchors-valid (CSS value for position-visibility ) §: Defined in CSS Anchor Positioning
anchors-visible (CSS value for position-visibility ) §: Defined in CSS Anchor Positioning
XRAnchor.anchorSpace (WebIDL attribute) §: Defined in WebXR Anchors
Atomics.and(typedArray, index, value) (WebIDL operation) §: Defined in ECMAScript
<angle> (CSS value for image-orientation ) §: Defined in CSS Images 3; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
<angle> (CSS type) §: Defined in CSS Values 3 , CSS Values 4; Referenced in CSS Conditional Values 1, CSS Shapes 2, CSS Color 4, CSS Color 5, CSS Fonts 4, CSS Images 3, CSS Properties and Values API 1, CSS Transforms 1, CSS Transforms 2, CSS Typed OM 1, CSS Writing Modes 3, CSS Writing Modes 4, CSSOM, Filter Effects 1, Motion Path 1; Related terms: CSS value deg, CSS value grad, CSS value rad, CSS value turn
<angle> (concept) §: Defined in CSS 2.1; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
angle (CSS value for corner-shape ) §: Defined in CSS Borders and Box Decorations 4
"angle" (value for CSSNumericBaseType WebIDL enumeration) §: Defined in CSS Typed OM 1
angle (CSS value for attr() ) §: Defined in CSS Values 5
CSSNumericType.angle (WebIDL dictionary member) §: Defined in CSS Typed OM 1
CSSRotate.angle (WebIDL attribute) §: Defined in CSS Typed OM 1
ScreenOrientation.angle (WebIDL attribute) §: Defined in Screen Orientation
SVGTransform.angle (WebIDL attribute) §: Defined in SVG 2
<angle-percentage> (CSS type) §: Defined in CSS Values 3 , CSS Values 4; Referenced in CSS Typed OM 1
<angular-color-hint> (CSS type) §: Defined in CSS Images 4
<angular-color-stop> (CSS type) §: Defined in CSS Images 4
<angular-color-stop-list> (CSS type) §: Defined in CSS Images 4
GamepadPose.angularAcceleration (WebIDL attribute) §: Defined in Gamepad Extensions
GamepadPose.angularVelocity (WebIDL attribute) §: Defined in Gamepad Extensions
XRPose.angularVelocity (WebIDL attribute) §: Defined in WebXR Device API
Animatable (WebIDL interface) §: Defined in Web Animations; Related terms: Animatable.animate(keyframes, options), Animatable.getAnimations(), Animatable.getAnimations(options); see also WebIDLPedia
animate (markup element) §: Defined in SVG Animations 2; Referenced in CSS Masking 1, CSS Transforms 1, CSS Transforms 2, Filter Effects 1; Related terms: markup attribute accumulate, markup attribute additive, markup attribute attributeName, markup attribute begin, markup attribute dur, markup attribute end, markup attribute fill, markup attribute from, markup attribute href, markup attribute keyPoints, markup attribute keySplines, markup attribute keyTimes, markup attribute max, markup attribute min, markup attribute onbegin, markup attribute onend, markup attribute onrepeat, markup attribute origin, markup attribute repeatCount, markup attribute repeatDur, markup attribute requiredExtensions, markup attribute restart, markup attribute rotate, markup attribute systemLanguage, markup attribute values
Animatable.animate(keyframes, options) (WebIDL operation) §: Defined in Web Animations; Referenced in Scroll-driven Animations
<animateable-feature> (CSS type) §: Defined in CSS Will Change 1
ImageTrack.[[animated]] (internal slot) §
ImageTrack.[[animated]] (internal slot) §: Defined in WebCodecs , WebCodecs
animated image document (concept) §: Defined in SVG Integration
SVGUseElement.animatedInstanceRoot (WebIDL attribute) §: Defined in SVG 2
SVGAnimatedPoints.animatedPoints (WebIDL attribute) §: Defined in SVG 2
animateMotion (markup element) §: Defined in SVG Animations 2; Referenced in CSS Masking 1
animateTransform (markup element) §: Defined in SVG Animations 2; Referenced in CSS Masking 1, Filter Effects 1
animation (CSS property) §: Defined in CSS Animations 1; Referenced in Compatibility, CSS Snapshot 2022, CSS Snapshot 2023, CSS Animations 2, CSS Color 4, CSS Typed OM 1, CSS Values 3, CSS Values 4, Scroll-driven Animations
animation (concept) §: Defined in Web Animations; Referenced in CSS Anchor Positioning, CSS Animations 2, CSS Transitions 2, Scroll-driven Animations; Related terms: concept associated effect, concept current time, concept document for timing, concept hold time, concept play state, concept relevant, concept reset an animation’s pending tasks, concept set the associated effect of an animation, concept set the current time, concept set the timeline of an animation, concept silently set the current time, concept start time
Animation (WebIDL interface) §: Defined in Web Animations; Referenced in CSS Animation Worklet API, CSS Animations 2, CSS Transitions 2, Scroll-driven Animations, Web Animations 2; Related terms: undefinedcurrentTime, Animation.effect, Animation.finished, Animation.id, Animation.oncancel, Animation.onfinish, Animation.onremove, Animation.pending, Animation.playbackRate, Animation.playState, Animation.progress, Animation.rangeEnd, Animation.rangeStart, Animation.ready, Animation.replaceState, undefinedstartTime, Animation.timeline, new Animation(effect, timeline), Animation.cancel(), Animation.commitStyles(), Animation.finish(), Animation.pause(), Animation.persist(), Animation.play(), Animation.reverse(), Animation.updatePlaybackRate(playbackRate); see also WebIDLPedia
animation attachment range (concept) §: Defined in Scroll-driven Animations; Referenced in Web Animations 2
animation composite order (concept) §: Defined in Web Animations
animation frame (concept) §: Defined in Web Animations; Referenced in CSS Animations 2, CSS Transitions 2
Animation Origin (concept) §: Defined in CSS Cascading 3 , CSS Cascading 4 , CSS Cascading 5; Referenced in CSS Snapshot 2022, CSS Snapshot 2023, CSS Anchor Positioning, Web Animations
Animation type (concept) §: Defined in Web Animations; Referenced in CSS Display 4, CSS Containment 2, CSS Masking 1, CSS Transitions, CSS Transitions 2
animation-composition (CSS property) §: Defined in CSS Animations 2; Referenced in CSS Typed OM 1
animation-delay (CSS property) §: Defined in CSS Animations 1; Referenced in Compatibility, CSS Snapshot 2022, CSS Snapshot 2023, CSS Animations 2, Scroll-driven Animations
animation-direction (CSS property) §: Defined in CSS Animations 1; Referenced in Compatibility, CSS Snapshot 2022, CSS Snapshot 2023, CSS Animations 2; Related terms: CSS value alternate, CSS value alternate-reverse, CSS value normal, CSS value reverse
animation-duration (CSS property) §: Defined in CSS Animations 1 , CSS Animations 2; Referenced in Compatibility, CSS Snapshot 2022, CSS Snapshot 2023; Related terms: CSS value auto
animation-fill-mode (CSS property) §: Defined in CSS Animations 1; Referenced in Compatibility, CSS Snapshot 2022, CSS Snapshot 2023, CSS Animations 2, Web Animations; Related terms: CSS value backwards, CSS value both, CSS value forwards, CSS value none
animation-iteration-count (CSS property) §: Defined in CSS Animations 1; Referenced in Compatibility, CSS Snapshot 2022, CSS Snapshot 2023, CSS Animations 2, CSS Values 4, Scroll-driven Animations; Related terms: CSS value infinite
animation-name (CSS property) §: Defined in CSS Animations 1; Referenced in Compatibility, CSS Snapshot 2022, CSS Snapshot 2023, CSS Animations 2, CSS Scoping 1, CSS Values 3, CSS Values 4, Web Animations; Related terms: CSS value <keyframes-name>, CSS value none
animation-play-state (CSS property) §: Defined in CSS Animations 1; Referenced in Compatibility, CSS Snapshot 2022, CSS Snapshot 2023, CSS Animations 2; Related terms: CSS value paused, CSS value running
animation-range (CSS property) §: Defined in Scroll-driven Animations; Referenced in CSS Animations 2
animation-range-end (CSS property) §: Defined in Scroll-driven Animations; Referenced in Web Animations 2; Related terms: CSS value <timeline-range-name> <length-percentage>?, CSS value normal
animation-range-start (CSS property) §: Defined in Scroll-driven Animations; Referenced in Web Animations 2; Related terms: CSS value <timeline-range-name> <length-percentage>?, CSS value normal
animation-timeline (CSS property) §: Defined in CSS Animations 2; Referenced in Scroll-driven Animations; Related terms: CSS value auto, CSS value none
animation-timing-function (CSS property) §: Defined in CSS Animations 1; Referenced in Compatibility, CSS Snapshot 2022, CSS Snapshot 2023, CSS Animations 2, CSS Syntax 3, CSS Values 3, CSS Values 4
new Animation(effect, timeline) (WebIDL constructor) §: Defined in Web Animations; Referenced in Web Animations 2
animationcancel (event for GlobalEventHandlers ) §: Defined in CSS Animations 1; Referenced in CSS Animations 2
AnimationEffect (WebIDL interface) §: Defined in Web Animations; Referenced in CSS Animation Worklet API, CSS Animations 2, Web Animations 2; Related terms: AnimationEffect.nextSibling, AnimationEffect.parent, AnimationEffect.previousSibling, AnimationEffect.after(...effects), AnimationEffect.before(...effects), undefinedgetComputedTiming(), AnimationEffect.getTiming(), AnimationEffect.remove(), AnimationEffect.replace(...effects), AnimationEffect.updateTiming(timing); see also WebIDLPedia
animationend (event for GlobalEventHandlers ) §: Defined in CSS Animations 1; Referenced in CSS Animations 2
AnimationEvent (WebIDL interface) §: Defined in CSS Animations 1; Referenced in CSS Animations 2; Related terms: AnimationEvent.animationName, AnimationEvent.elapsedTime, AnimationEvent.pseudoElement, new AnimationEvent(type, animationEventInitDict); see also WebIDLPedia
new AnimationEvent(type, animationEventInitDict) (WebIDL constructor) §: Defined in CSS Animations 1
AnimationEventInit (WebIDL dictionary) §: Defined in CSS Animations 1; Related terms: AnimationEventInit.animationName, AnimationEventInit.elapsedTime, AnimationEventInit.pseudoElement; see also WebIDLPedia
AnimationFrameProvider (WebIDL interface) §: Defined in HTML; Referenced in HTMLVideoElement.requestVideoFrameCallback(); Related terms: AnimationFrameProvider.cancelAnimationFrame(handle), AnimationFrameProvider.requestAnimationFrame(callback); see also WebIDLPedia
animationiteration (event for GlobalEventHandlers ) §: Defined in CSS Animations 1; Referenced in CSS Animations 2
AnimationEvent.animationName (WebIDL attribute) §: Defined in CSS Animations 1
AnimationEventInit.animationName (WebIDL dictionary member) §: Defined in CSS Animations 1
CSSAnimation.animationName (WebIDL attribute) §: Defined in CSS Animations 2
AnimationNodeList (WebIDL interface) §: Defined in Web Animations 2; Related terms: AnimationNodeList.length, AnimationNodeList.item(index); see also WebIDLPedia
AnimationPlaybackEvent (WebIDL interface) §: Defined in Web Animations , Web Animations 2; Related terms: undefinedcurrentTime, undefinedtimelineTime, undefinedAnimationPlaybackEvent(type, eventInitDict); see also WebIDLPedia
new AnimationPlaybackEvent(type, eventInitDict) (WebIDL constructor) §
new AnimationPlaybackEvent(type, eventInitDict) (WebIDL constructor) §: Defined in Web Animations , Web Animations 2
AnimationPlaybackEventInit (WebIDL dictionary) §: Defined in Web Animations , Web Animations 2; Related terms: undefinedcurrentTime, undefinedtimelineTime; see also WebIDLPedia
AnimationPlayState (WebIDL enumeration) §: Defined in Web Animations; Related terms: value finished, value idle, value paused, value running; see also WebIDLPedia
AnimationReplaceState (WebIDL enumeration) §: Defined in Web Animations; Related terms: value active, value persisted, value removed; see also WebIDLPedia
animationstart (event for GlobalEventHandlers ) §: Defined in CSS Animations 1; Referenced in CSS Animations 2
AnimationTimeline (WebIDL interface) §: Defined in Web Animations; Referenced in CSS Animation Worklet API, Scroll-driven Animations, Web Animations 2; Related terms: undefinedcurrentTime, AnimationTimeline.duration, AnimationTimeline.play(effect); see also WebIDLPedia
animationWorklet (WebIDL attribute for CSS ) §: Defined in CSS Animation Worklet API
AnimationWorkletGlobalScope (WebIDL interface) §: Defined in CSS Animation Worklet API; Related terms: AnimationWorkletGlobalScope.registerAnimator(name, animatorCtor); see also WebIDLPedia
AnimatorInstanceConstructor (WebIDL callback) §: Defined in CSS Animation Worklet API
WorkletAnimation.animatorName (WebIDL attribute) §: Defined in CSS Animation Worklet API
SVGAnimatedAngle.animVal (WebIDL attribute) §: Defined in SVG 2
SVGAnimatedBoolean.animVal (WebIDL attribute) §: Defined in SVG 2
SVGAnimatedEnumeration.animVal (WebIDL attribute) §: Defined in SVG 2
SVGAnimatedInteger.animVal (WebIDL attribute) §: Defined in SVG 2
SVGAnimatedLength.animVal (WebIDL attribute) §: Defined in SVG 2
SVGAnimatedLengthList.animVal (WebIDL attribute) §: Defined in SVG 2
SVGAnimatedNumber.animVal (WebIDL attribute) §: Defined in SVG 2
SVGAnimatedNumberList.animVal (WebIDL attribute) §: Defined in SVG 2
SVGAnimatedPreserveAspectRatio.animVal (WebIDL attribute) §: Defined in SVG 2; Referenced in CSS Transforms 1
SVGAnimatedRect.animVal (WebIDL attribute) §: Defined in SVG 2
SVGAnimatedString.animVal (WebIDL attribute) §: Defined in SVG 2
SVGAnimatedTransformList.animVal (WebIDL attribute) §: Defined in SVG 2
"annexb" (value for AvcBitstreamFormat WebIDL enumeration) §: Defined in H.264
"annexb" (value for HevcBitstreamFormat WebIDL enumeration) §: Defined in H.265
annotated types (concept) §: Defined in Web IDL; Related terms: concept inner type
@annotation (CSS @rule for @font-feature-values ) §: Defined in CSS Fonts 4; Referenced in CSS Snapshot 2023
annotation (markup element) §: Defined in MathML Core; Related terms: markup attribute encoding
CSSFontFeatureValuesRule.annotation (WebIDL attribute) §: Defined in CSS Fonts 4
annotation pairing (concept) §: Defined in HTML Ruby Markup Extensions
annotation-xml (markup element) §: Defined in MathML Core; Referenced in HTML; Related terms: markup attribute encoding
annotation(<feature-value-name>) (CSS value for font-variant-alternates ) §: Defined in CSS Fonts 4; Referenced in CSS Snapshot 2023
announce the rtcdatachannel as open (algorithm) §: Defined in WebRTC 1.0
anonymization policy (concept for prefetch record ) §: Defined in Prefetch
anonymous (concept for CSS ) §: Defined in CSS Display 4 , CSS Display 3; Referenced in CSS Snapshot 2022, CSS Snapshot 2023, CSS Flexbox 1, CSS Grid Layout 1, CSS Grid Layout 2, CSS Inline Layout 3, CSS Layout API 1, CSS Lists 3, CSS Table 3, CSS Text Decoration 3, CSS Text Decoration 4, CSSOM View
anonymous (value for crossorigin attribute of audio element, crossorigin attribute of img element, crossorigin attribute of link element, crossorigin attribute of script, crossorigin attribute of video element ) §: Defined in HTML
anonymous (CSS value for <request-url-modifier> ) §: Defined in CSS Values 5
anonymous (concept) §: Defined in CSS 2.1; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
anonymous inline boxes (concept) §: Defined in CSS 2.1; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
"answer" (value for RTCSdpType WebIDL enumeration) §: Defined in WebRTC 1.0
SmartCardConnectionStatus.answerToReset (WebIDL dictionary member) §: Defined in Web Smart Card API
SmartCardReaderStateOut.answerToReset (WebIDL dictionary member) §: Defined in Web Smart Card API
<antecedent> (CSS type) §: Defined in CSS Conditional Values 1
XRWebGLLayer.antialias (WebIDL attribute) §: Defined in WebXR Device API
XRWebGLLayerInit.antialias (WebIDL dictionary member) §: Defined in WebXR Device API
WebTransport.[[AnticipatedConcurrentIncomingBidirectionalStreams]] (internal slot) §: Defined in WebTransport
WebTransport.anticipatedConcurrentIncomingBidirectionalStreams (WebIDL attribute) §: Defined in WebTransport
WebTransportOptions.anticipatedConcurrentIncomingBidirectionalStreams (WebIDL dictionary member) §: Defined in WebTransport
WebTransport.[[AnticipatedConcurrentIncomingUnidirectionalStreams]] (internal slot) §: Defined in WebTransport
WebTransport.anticipatedConcurrentIncomingUnidirectionalStreams (WebIDL attribute) §: Defined in WebTransport
WebTransportOptions.anticipatedConcurrentIncomingUnidirectionalStreams (WebIDL dictionary member) §: Defined in WebTransport
DeprecationReportBody.anticipatedRemoval (WebIDL attribute) §: Defined in Deprecation Reporting
antiquewhite (concept) §: Defined in CSS Color 3; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
antiquewhite (CSS value for <color>, <named-color> type ) §: Defined in CSS Color 4
any (WebIDL interface) §: Defined in Web IDL; Referenced in Console, DOM, Fetch, Notifications API, Streams, Web NFC API, WebAssembly JavaScript Interface: Content Security Policy, WebAssembly JavaScript Interface: ESM Integration, WebAssembly JavaScript Interface: Exception Handling, WebAssembly JavaScript Interface: Promise Integration, WebAssembly JavaScript Interface: JS String Builtins, WebAssembly JavaScript Interface: Type Reflection, Web Bluetooth, Web IDL, Observable, Prioritized Task Scheduling, Shared Storage API, Protected Audience, Web App Launch Handler API, CSS Animation Worklet API, CSS Images 4, CSS Layout API 1, CSS View Transitions 1, Indexed DB 3.0, JSON-LD 1.1 Processing Algorithms and API, Push API, Service Workers, Trusted Types, User Timing, WebAssembly JavaScript Interface, Web Locks API, Web Cryptography API, WebGPU, WebRTC Encoded Transform, WebTransport, XMLHttpRequest; see also WebIDLPedia
any (CSS value for calc-size() ) §: Defined in CSS Values 5
"any" (value for OrientationLockType WebIDL enumeration) §: Defined in Screen Orientation
XPathResult.ANY_TYPE (WebIDL constant) §: Defined in DOM
XPathResult.ANY_UNORDERED_NODE_TYPE (WebIDL constant) §: Defined in DOM
any-hover (CSS descriptor for @media ) §: Defined in Media Queries 4 , Media Queries 5
:any-link (CSS selector) §: Defined in Selectors 4; Referenced in Quirks Mode, Speculation Rules
any-pointer (CSS descriptor for @media ) §: Defined in Media Queries 4 , Media Queries 5
<any-value> (CSS type) §: Defined in CSS Syntax 3; Referenced in CSS Linked Parameters, CSS Values 4, Media Queries 4, Media Queries 5, Selectors 4
Promise.any(iterable) (WebIDL operation) §: Defined in ECMAScript
TaskSignal.any(signals, init) (WebIDL operation) §: Defined in Prioritized Task Scheduling
AbortSignal.any(signals) (WebIDL operation) §: Defined in DOM
AnyExternType (WebIDL dictionary) §: Defined in WebAssembly JavaScript Interface: Type Reflection; Related terms: AnyExternType.element, AnyExternType.maximum, AnyExternType.minimum, AnyExternType.mutable, AnyExternType.parameters, AnyExternType.results, AnyExternType.value; see also WebIDLPedia
"anyfunc" (value for TableKind WebIDL enumeration) §: Defined in WebAssembly JavaScript Interface: Content Security Policy , WebAssembly JavaScript Interface: ESM Integration , WebAssembly JavaScript Interface: Exception Handling , WebAssembly JavaScript Interface: Promise Integration , WebAssembly JavaScript Interface: JS String Builtins , WebAssembly JavaScript Interface: Type Reflection , WebAssembly JavaScript Interface: Threading , WebAssembly JavaScript Interface
"anyfunc" (value for ValueType WebIDL enumeration) §: Defined in WebAssembly JavaScript Interface: Content Security Policy , WebAssembly JavaScript Interface: ESM Integration , WebAssembly JavaScript Interface: Exception Handling , WebAssembly JavaScript Interface: Promise Integration , WebAssembly JavaScript Interface: JS String Builtins , WebAssembly JavaScript Interface: Type Reflection , WebAssembly JavaScript Interface: Threading , WebAssembly JavaScript Interface
anywhere (CSS value for line-break ) §: Defined in CSS Text 3 , CSS Text 4; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
anywhere (CSS value for overflow-wrap ) §: Defined in CSS Text 3 , CSS Text 4; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
API base URL (concept for environment settings object ) §: Defined in HTML; Referenced in Fetch, Notifications API, URL Pattern, WebDriver BiDi, WebSockets, Content Index, Cookie Store API, Beacon, CSS Values 4, Image Resource, Service Workers, Web Share API, WebTransport
app-region (concept) §: Defined in Manifest Incubations
AppBannerPromptOutcome (WebIDL enumeration) §: Defined in Manifest Incubations; Related terms: value accepted, value dismissed; see also WebIDLPedia
NavigatorID.appCodeName (WebIDL attribute) §: Defined in HTML
appearance (CSS property) §: Defined in CSS User Interface 4; Referenced in CSS Typed OM 1; Related terms: CSS type <compat-auto>, CSS type <compat-special>, CSS value auto, CSS value button, CSS value checkbox, CSS value listbox, CSS value menulist, CSS value menulist-button, CSS value meter, CSS value none, CSS value progress-bar, CSS value radio, CSS value searchfield, CSS value textarea, CSS value textfield
BluetoothAdvertisingEvent.appearance (WebIDL attribute) §: Defined in Web Bluetooth
BluetoothAdvertisingEventInit.appearance (WebIDL dictionary member) §: Defined in Web Bluetooth
appearance of a cross-fade() (concept) §: Defined in CSS Images 4
append (concept) §: Defined in DOM; Referenced in HTML, Navigational-Tracking Mitigations, Web NFC API, Fenced Frame
append (concept for header list ) §: Defined in Fetch; Referenced in Web Share Target API, WebSockets, Client Hints Infrastructure, Shared Storage API, Loading Signed Exchanges, Content Security Policy: Embedded Enforcement, Service Workers, Upgrade Insecure Requests
append (concept for Headers ) §: Defined in Fetch
append (concept for list ) §: Defined in Infra; Referenced in Console, DOM, Encoding, Fetch, File System, HTML, Notifications API, Private Aggregation API, Topics API, Streams, URL, URL Pattern, Long Animation Frames API, Web Share Target API, WebDriver BiDi, WebAssembly JavaScript Interface: Content Security Policy, WebAssembly JavaScript Interface: ESM Integration, WebAssembly JavaScript Interface: Exception Handling, WebAssembly JavaScript Interface: Promise Integration, WebAssembly JavaScript Interface: JS String Builtins, WebAssembly JavaScript Interface: Type Reflection, WebAssembly JavaScript Interface: Threading, Web Bluetooth, Web IDL, Attribution Reporting, Background Fetch, Content Index, Cookie Store API, Fenced Frame, File System Access, Get Installed Related Apps API, Handwriting Recognition API, Layout Instability, Local Font Access, Manifest Incubations, Prefetch, Prerendering Revamped, Speculation Rules, Observable, Page Lifecycle, Measure Memory API, Web Periodic Background Synchronization, HTML Sanitizer API, URL Fragment Text Directives, Web Serial API, Shared Storage API, Storage Buckets API, Private State Token API, Protected Audience, User-Agent Client Hints, Web Smart Card API, WebHID API, Loading Signed Exchanges, WebUSB API, Web Application Manifest, Clear Site Data, Compute Pressure 1, Contact Picker API, Content Security Policy 3, CSS Layout API 1, CSS Painting API 1, CSS Properties and Values API 1, CSS Shadow Parts, CSS Transforms 2, CSS Typed OM 1, CSS View Transitions 1, CSSOM, Federated Credential Management API, Gamepad, Geolocation, Indexed DB 3.0, Media Source Extensions™, MiniApp Manifest, Device Orientation and Motion, Paint Timing, Payment Method Manifest, Performance Timeline, Permissions Policy, Permissions, Publication Manifest, Screen Wake Lock API, Secure Payment Confirmation, Server Timing, Service Workers, SRI, WebAssembly JavaScript Interface, Web Locks API, Web Authentication, WebGPU, Web Neural Network API, WebRTC 1.0, WebXR Device API, Window Management, XMLHttpRequest
append (concept for set ) §: Defined in Infra; Referenced in DOM, CSS Positioned Layout 4, Fetch, File System, Fullscreen API, HTML, Private Aggregation API, Topics API, Navigational-Tracking Mitigations, Storage, Streams, WebDriver BiDi, WebAssembly JavaScript Interface: ESM Integration, Web IDL, Attribution Reporting, Client Hints Infrastructure, Cookie Store API, Fenced Frame, Keyboard Lock, Speculation Rules, HTML Sanitizer API, Prioritized Task Scheduling, Shared Storage API, Soft Navigations, Protected Audience, Web Smart Card API, Loading Signed Exchanges, Web Application Manifest, Compute Pressure 1, Credential Management 1, Content Security Policy: Embedded Enforcement, Content Security Policy 3, CSS Lists 3, CSS Properties and Values API 1, CSS View Transitions 1, Federated Credential Management API, Generic Sensor API, Indexed DB 3.0, Largest Contentful Paint, Device Orientation and Motion, Paint Timing, Payment Method Manifest, Payment Request API, Publication Manifest, Service Workers, Trusted Types, Web Locks API, Web Authentication, WebGPU, Web Neural Network API, WebTransport
append an attribute (concept) §: Defined in DOM; Referenced in HTML
append an entry to the contribution cache (concept) §: Defined in Private Aggregation API
append client hints to request (algorithm) §: Defined in Client Hints Infrastructure; Referenced in Responsive Image Client Hints, User-Agent Client Hints
Append Error (concept) §: Defined in Media Source Extensions™
append the Fetch metadata headers for a request (algorithm) §: Defined in Fetch Metadata; Referenced in Fetch
GroupEffect.append(...effects) (WebIDL operation) §: Defined in Web Animations 2
ParentNode.append(...nodes) (WebIDL operation) §: Defined in DOM
SharedStorage.append(key, value) (WebIDL operation) §: Defined in Shared Storage API
FormData.append(name, blobValue, filename) (WebIDL operation) §: Defined in XMLHttpRequest
FormData.append(name, value) (WebIDL operation) §: Defined in XMLHttpRequest
Headers.append(name, value) (WebIDL operation) §: Defined in Fetch
URLSearchParams.append(name, value) (WebIDL operation) §: Defined in URL
StylePropertyMap.append(property, ...values) (WebIDL operation) §: Defined in CSS Typed OM 1
SourceBuffer.appendBuffer() (WebIDL operation) §: Defined in Media Source Extensions™
Node.appendChild(node) (WebIDL operation) §: Defined in DOM; Referenced in HTML
CharacterData.appendData(data) (WebIDL operation) §: Defined in DOM
MediaList.appendMedium(medium) (WebIDL operation) §: Defined in CSSOM
AppendMode (WebIDL enumeration) §: Defined in Media Source Extensions™; Related terms: value segments, value sequence; see also WebIDLPedia
CSSKeyframesRule.appendRule(rule) (WebIDL operation) §: Defined in CSS Animations 1
SourceBuffer.appendWindowEnd (WebIDL attribute) §: Defined in Media Source Extensions™
SourceBuffer.appendWindowStart (WebIDL attribute) §: Defined in Media Source Extensions™
AuthenticationExtensionsClientInputs.appid (WebIDL dictionary member) §: Defined in Web Authentication
AuthenticationExtensionsClientOutputs.appid (WebIDL dictionary member) §: Defined in Web Authentication
AuthenticationExtensionsClientInputs.appidExclude (WebIDL dictionary member) §: Defined in Web Authentication
AuthenticationExtensionsClientOutputs.appidExclude (WebIDL dictionary member) §: Defined in Web Authentication
appinstalled (event) §: Defined in Manifest Incubations
applet (markup element) §: Defined in HTML
Document.applets (WebIDL attribute) §: Defined in HTML
OpusEncoderConfig.application (WebIDL dictionary member) §: Defined in Opus WebCodecs Registration
application context (concept) §: Defined in Web Application Manifest; Referenced in Media Queries 5
Application internal identifiers (concept) §: Defined in Internationalization Glossary
application manifest media type (concept) §: Defined in Web Application Manifest
application-name (value for name attribute of meta element ) §: Defined in HTML
application/manifest+json (concept) §: Defined in Web Application Manifest
application/x-www-form-urlencoded (value for enctype attribute of button element, enctype attribute of form element ) §: Defined in HTML
application/x-www-form-urlencoded (concept) §: Defined in URL; Referenced in HTML, Web Share Target API, No-Vary-Search
PushSubscriptionOptions.applicationServerKey (WebIDL attribute) §: Defined in Push API
PushSubscriptionOptionsInit.applicationServerKey (WebIDL dictionary member) §: Defined in Push API
applied (concept) §: Defined in Web Application Manifest
Apply brotli patch (algorithm) §: Defined in Incremental Font Transfer
Apply glyph keyed patch (algorithm) §: Defined in Incremental Font Transfer
Apply per table brotli patch (algorithm) §: Defined in Incremental Font Transfer
apply request modifiers from URL value (concept) §: Defined in CSS Values 5
apply the percent hint (concept) §: Defined in CSS Typed OM 1
apply to (concept for CSS ) §: Defined in CSS Cascading 4 , CSS Cascading 5; Referenced in CSS Snapshot 2022, CSS Snapshot 2023, CSS User Interface 4
Reflect.apply(target, thisArgument, argumentsList) (WebIDL operation) §: Defined in ECMAScript
Function.apply(thisArg, argArray) (WebIDL operation) §: Defined in ECMAScript
ApplyConstraints algorithm (algorithm) §: Defined in Media Capture and Streams
ConstrainablePattern.applyConstraints() (WebIDL operation) §: Defined in Media Capture and Streams
MediaStreamTrack.applyConstraints() (WebIDL operation) §: Defined in Media Capture and Streams; Referenced in MediaStream Image Capture, MediaStreamTrack Insertable Media Processing using Streams
ApplyStringOrNumericBinaryOperator (algorithm) §: Defined in ECMAScript
NavigatorID.appName (WebIDL attribute) §: Defined in HTML
IdentityProviderAccount.approved_clients (WebIDL dictionary member) §: Defined in Federated Credential Management API
NavigatorID.appVersion (WebIDL attribute) §: Defined in HTML; Referenced in WebXR Device API
AppWorkspace (concept) §: Defined in CSS Color 3; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
AppWorkspace (CSS value for <color>, <deprecated-color> type ) §: Defined in CSS Color 4
aqua (concept) §: Defined in CSS Color 3; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
aqua (CSS value for <color>, <named-color> type ) §: Defined in CSS Color 4 , CSS 2.2
aquamarine (concept) §: Defined in CSS Color 3; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
aquamarine (CSS value for <color>, <named-color> type ) §: Defined in CSS Color 4
arabic-indic (CSS value for <counter-style-name> ) §: Defined in CSS Counter Styles 3; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
arbitrary substitution function (concept) §: Defined in CSS Variables 1; Referenced in CSS Snapshot 2022, CSS Snapshot 2023, CSS Anchor Positioning, CSS Values 5
arc (CSS value for shape() ) §: Defined in CSS Shapes 2; Related terms: CSS value ccw, CSS value cw, CSS value large, CSS value small
<arc-command> (CSS type for shape() ) §: Defined in CSS Shapes 2
<arc-size> (CSS type for shape() ) §: Defined in CSS Shapes 2
<arc-sweep> (CSS type for shape() ) §: Defined in CSS Shapes 2
CanvasPath.arc(x, y, radius, startAngle, endAngle, counterclockwise) (WebIDL operation) §: Defined in HTML
GPUAdapterInfo.architecture (WebIDL attribute) §: Defined in WebGPU
UADataValues.architecture (WebIDL dictionary member) §: Defined in User-Agent Client Hints
archive (markup attribute for object ) §: Defined in HTML
HTMLObjectElement.archive (WebIDL attribute) §: Defined in HTML
archive MIME type (concept) §: Defined in MIME Sniffing
arcs (CSS value for stroke-linejoin ) §: Defined in CSS Fill and Stroke 3
arcs linejoin (concept) §: Defined in CSS Fill and Stroke 3
CanvasPath.arcTo(x1, y1, x2, y2, radius) (WebIDL operation) §: Defined in HTML
area (markup element) §: Defined in HTML; Referenced in DOM, Speculation Rules, EPUB 3.3, HTML Accessibility API Mappings 1.0, ARIA in HTML, Referrer Policy, Selectors 4; Related terms: markup attribute alt, markup attribute coords, markup attribute download, markup attribute hreflang, markup attribute hreflang, markup attribute nohref, markup attribute ping, markup attribute referrerpolicy, markup attribute rel, markup attribute shape, markup attribute target, markup attribute type, markup attribute type
HTMLMapElement.areas (WebIDL attribute) §: Defined in HTML
arg (markup attribute) §: Defined in MathML Core
MLOpSupportLimits.argMax (WebIDL dictionary member) §: Defined in Web Neural Network API
MLGraphBuilder.argMax(input, axis, options) (WebIDL operation) §: Defined in Web Neural Network API
MLOpSupportLimits.argMin (WebIDL dictionary member) §: Defined in Web Neural Network API
MLGraphBuilder.argMin(input, axis, options) (WebIDL operation) §: Defined in Web Neural Network API
CSSParserFunction.args (WebIDL attribute) §: Defined in CSS Parser API
arguments exotic object (concept for ECMAScript ) §: Defined in ECMAScript
ARIA attributes (concept) §: Defined in SVG 2; Referenced in SVG Animations 2
ARIAMixin.ariaActiveDescendantElement (WebIDL attribute) §
ARIAMixin.ariaActiveDescendantElement (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaAtomic (WebIDL attribute) §
ARIAMixin.ariaAtomic (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaAutoComplete (WebIDL attribute) §
ARIAMixin.ariaAutoComplete (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaBrailleLabel (WebIDL attribute) §
ARIAMixin.ariaBrailleLabel (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaBrailleRoleDescription (WebIDL attribute) §
ARIAMixin.ariaBrailleRoleDescription (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaBusy (WebIDL attribute) §
ARIAMixin.ariaBusy (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaChecked (WebIDL attribute) §
ARIAMixin.ariaChecked (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaColCount (WebIDL attribute) §
ARIAMixin.ariaColCount (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaColIndex (WebIDL attribute) §
ARIAMixin.ariaColIndex (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaColIndexText (WebIDL attribute) §
ARIAMixin.ariaColIndexText (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaColSpan (WebIDL attribute) §
ARIAMixin.ariaColSpan (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaControlsElements (WebIDL attribute) §
ARIAMixin.ariaControlsElements (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaCurrent (WebIDL attribute) §
ARIAMixin.ariaCurrent (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaDescribedByElements (WebIDL attribute) §
ARIAMixin.ariaDescribedByElements (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaDescription (WebIDL attribute) §
ARIAMixin.ariaDescription (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaDetailsElements (WebIDL attribute) §
ARIAMixin.ariaDetailsElements (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaDisabled (WebIDL attribute) §
ARIAMixin.ariaDisabled (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaErrorMessageElements (WebIDL attribute) §
ARIAMixin.ariaErrorMessageElements (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaExpanded (WebIDL attribute) §
ARIAMixin.ariaExpanded (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaFlowToElements (WebIDL attribute) §
ARIAMixin.ariaFlowToElements (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaHasPopup (WebIDL attribute) §
ARIAMixin.ariaHasPopup (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaHidden (WebIDL attribute) §
ARIAMixin.ariaHidden (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaInvalid (WebIDL attribute) §
ARIAMixin.ariaInvalid (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaKeyShortcuts (WebIDL attribute) §
ARIAMixin.ariaKeyShortcuts (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaLabel (WebIDL attribute) §
ARIAMixin.ariaLabel (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaLabelledByElements (WebIDL attribute) §
ARIAMixin.ariaLabelledByElements (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaLevel (WebIDL attribute) §
ARIAMixin.ariaLevel (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaLive (WebIDL attribute) §
ARIAMixin.ariaLive (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin (WebIDL interface) §: Defined in WAI-ARIA , WAI-ARIA; Related terms: undefinedariaActiveDescendantElement, undefinedariaAtomic, undefinedariaAutoComplete, undefinedariaBrailleLabel, undefinedariaBrailleRoleDescription, undefinedariaBusy, undefinedariaChecked, undefinedariaColCount, undefinedariaColIndex, undefinedariaColIndexText, undefinedariaColSpan, undefinedariaControlsElements, undefinedariaCurrent, undefinedariaDescribedByElements, undefinedariaDescription, undefinedariaDetailsElements, undefinedariaDisabled, undefinedariaErrorMessageElements, undefinedariaExpanded, undefinedariaFlowToElements, undefinedariaHasPopup, undefinedariaHidden, undefinedariaInvalid, undefinedariaKeyShortcuts, undefinedariaLabel, undefinedariaLabelledByElements, undefinedariaLevel, undefinedariaLive, undefinedariaModal, undefinedariaMultiLine, undefinedariaMultiSelectable, undefinedariaOrientation, undefinedariaOwnsElements, undefinedariaPlaceholder, undefinedariaPosInSet, undefinedariaPressed, undefinedariaReadOnly, undefinedariaRequired, undefinedariaRoleDescription, undefinedariaRowCount, undefinedariaRowIndex, undefinedariaRowIndexText, undefinedariaRowSpan, undefinedariaSelected, undefinedariaSetSize, undefinedariaSort, undefinedariaValueMax, undefinedariaValueMin, undefinedariaValueNow, undefinedariaValueText, undefinedrole; see also WebIDLPedia
ARIAMixin.ariaModal (WebIDL attribute) §
ARIAMixin.ariaModal (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaMultiLine (WebIDL attribute) §
ARIAMixin.ariaMultiLine (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaMultiSelectable (WebIDL attribute) §
ARIAMixin.ariaMultiSelectable (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaOrientation (WebIDL attribute) §
ARIAMixin.ariaOrientation (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaOwnsElements (WebIDL attribute) §
ARIAMixin.ariaOwnsElements (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaPlaceholder (WebIDL attribute) §
ARIAMixin.ariaPlaceholder (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaPosInSet (WebIDL attribute) §
ARIAMixin.ariaPosInSet (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaPressed (WebIDL attribute) §
ARIAMixin.ariaPressed (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaReadOnly (WebIDL attribute) §
ARIAMixin.ariaReadOnly (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaRequired (WebIDL attribute) §
ARIAMixin.ariaRequired (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaRoleDescription (WebIDL attribute) §
ARIAMixin.ariaRoleDescription (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaRowCount (WebIDL attribute) §
ARIAMixin.ariaRowCount (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaRowIndex (WebIDL attribute) §
ARIAMixin.ariaRowIndex (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaRowIndexText (WebIDL attribute) §
ARIAMixin.ariaRowIndexText (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaRowSpan (WebIDL attribute) §
ARIAMixin.ariaRowSpan (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaSelected (WebIDL attribute) §
ARIAMixin.ariaSelected (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaSetSize (WebIDL attribute) §
ARIAMixin.ariaSetSize (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaSort (WebIDL attribute) §
ARIAMixin.ariaSort (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaValueMax (WebIDL attribute) §
ARIAMixin.ariaValueMax (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaValueMin (WebIDL attribute) §
ARIAMixin.ariaValueMin (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaValueNow (WebIDL attribute) §
ARIAMixin.ariaValueNow (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
ARIAMixin.ariaValueText (WebIDL attribute) §
ARIAMixin.ariaValueText (WebIDL attribute) §: Defined in WAI-ARIA , WAI-ARIA
arithmetic (value for operator attribute of feComposite ) §: Defined in Filter Effects 1
armenian (CSS value for <counter-style-name> ) §: Defined in CSS Counter Styles 3; Referenced in CSS Snapshot 2022, CSS Snapshot 2023, CSS Speech 1
armenian (CSS value) §: Defined in CSS 2.1; Referenced in CSS Snapshot 2022, CSS Snapshot 2023
armenian (CSS value for list-style-type ) §: Defined in CSS 2.2
Array (WebIDL interface) §: Defined in ECMAScript; Referenced in Streams, Accelerated Shape Detection in Images, Indexed DB 3.0; Related terms: new Array(...values), Array.at(index), Array.concat(...items), Array.copyWithin(target, start, end), Array.entries(), Array.every(callback, thisArg), Array.fill(value, start, end), Array.filter(callback, thisArg), Array.find(predicate, thisArg), Array.findIndex(predicate, thisArg), Array.findLast(predicate, thisArg), Array.findLastIndex(predicate, thisArg), Array.flat(depth), Array.flatMap(mapperFunction, thisArg), Array.forEach(callback, thisArg), Array.from(items, mapper, thisArg), Array.includes(searchElement, fromIndex), Array.indexOf(searchElement, fromIndex), Array.isArray(arg), Array.join(separator), Array.keys(), Array.lastIndexOf(searchElement, fromIndex), Array.map(callback, thisArg), Array.of(...items), Array.pop(), Array.push(...items), Array.reduce(callback, initialValue), Array.reduceRight(callback, initialValue), Array.reverse(), Array.shift(), Array.slice(start, end), Array.some(callback, thisArg), Array.sort(comparator), Array.splice(start, deleteCount, ...items), Array.toLocaleString(reserved1, reserved2), Array.toReversed(), Array.toSorted(comparator), Array.toSpliced(start, skipCount, ...items), Array.toString(), Array.unshift(...items), Array.values(), Array.with(index, value); see also WebIDLPedia
Array exotic object (concept for ECMAScript ) §: Defined in ECMAScript; Referenced in Indexed DB 3.0
array index (concept for ECMAScript ) §: Defined in ECMAScript; Referenced in Web IDL
array layer count (algorithm) §: Defined in WebGPU
array-like object (concept for ECMAScript ) §: Defined in ECMAScript; Referenced in ECMAScript Internationalization API, 2022, JSON.parse source text access
Array.prototype %Symbol.iterator% () (WebIDL operation for Array.prototype [ %Symbol.iterator% ] ( ) ) §: Defined in ECMAScript
%Array.prototype% (WebIDL interface) §: Defined in ECMAScript; Referenced in HTML, Web IDL; see also WebIDLPedia
new Array(...values) (WebIDL constructor) §: Defined in ECMAScript
%Array% (WebIDL interface) §: Defined in ECMAScript; Referenced in ECMAScript Async Explicit Resource Management, ECMAScript Explicit Resource Management, Source Phase Imports; see also WebIDLPedia
ArrayBuffer (WebIDL interface) §: Defined in Web IDL; Referenced in Encoding, Fetch, CTAP, HTML, Web Bluetooth Scanning, WebSockets, Direct Sockets API, Web Smart Card API, Secure Curves in the Web Cryptography API, Loading Signed Exchanges, WebUSB API, Encrypted Media Extensions, File API, Indexed DB 3.0, Presentation API, Push API, Service Workers, Web Audio API, Web Authentication, WebCodecs, Web Cryptography API, WebGPU, Web Neural Network API, WebRTC Encoded Transform, WebRTC 1.0, WebTransport, WebXR Depth Sensing, XMLHttpRequest; Related terms: concept create, concept detach, concept transfer, concept write, ArrayBuffer.byteLength, ArrayBuffer.detached, ArrayBuffer.maxByteLength, ArrayBuffer.resizable, new ArrayBuffer(length, options), ArrayBuffer.isView(arg), ArrayBuffer.resize(newLength), ArrayBuffer.slice(start, end), ArrayBuffer.transfer(newLength), ArrayBuffer.transferToFixedLength(newLength); see also WebIDLPedia
"arraybuffer" (value for BinaryType WebIDL enumeration) §: Defined in WebSockets; Referenced in WebRTC 1.0
"arraybuffer" (value for XMLHttpRequestResponseType WebIDL enumeration) §: Defined in XMLHttpRequest
%ArrayBuffer.prototype% (WebIDL interface) §: Defined in ECMAScript; see also WebIDLPedia
Blob.arrayBuffer() (WebIDL operation) §: Defined in File API
Body.arrayBuffer() (WebIDL operation) §: Defined in Fetch
PushMessageData.arrayBuffer() (WebIDL operation) §: Defined in Push API
new ArrayBuffer(length, options) (WebIDL constructor) §: Defined in ECMAScript
%ArrayBuffer% (WebIDL interface) §: Defined in ECMAScript; Referenced in Streams, ECMAScript Async Explicit Resource Management, ECMAScript Explicit Resource Management, Source Phase Imports, Web IDL; see also WebIDLPedia
ArrayBufferByteLength (algorithm) §: Defined in ECMAScript
ArrayBufferCopyAndDetach (algorithm) §: Defined in ECMAScript
ArrayBufferView (WebIDL type alias) §: Defined in Web IDL; Referenced in Streams, WebSockets, Presentation API, Web Cryptography API, Web Neural Network API, WebRTC 1.0; Related terms: concept create, concept write; see also WebIDLPedia
ArrayCreate (algorithm) §: Defined in ECMAScript; Referenced in HTML, ECMAScript Internationalization API, 2022, ECMAScript Async Explicit Resource Management, ECMAScript Explicit Resource Management, Intl.DurationFormat, Temporal, Web IDL
%ArrayIteratorPrototype% (WebIDL interface) §: Defined in ECMAScript; see also WebIDLPedia
GPUTextureViewDescriptor.arrayLayerCount (WebIDL dictionary member) §: Defined in WebGPU
ArraySetLength (algorithm) §: Defined in ECMAScript
ArraySpeciesCreate (algorithm) §: Defined in ECMAScript
GPUVertexBufferLayout.arrayStride (WebIDL dictionary member) §: Defined in WebGPU
article (markup element) §: Defined in HTML; Referenced in HTML Accessibility API Mappings 1.0, ARIA in HTML, WAI-ARIA, WAI-ARIA
"article" (value for ContentCategory WebIDL enumeration) §: Defined in Content Index
MediaMetadata.artist (WebIDL attribute) §: Defined in Media Session
MediaMetadataInit.artist (WebIDL dictionary member) §: Defined in Media Session
ChapterInformation.artwork (WebIDL attribute) §: Defined in Media Session
ChapterInformationInit.artwork (WebIDL dictionary member) §: Defined in Media Session
MediaMetadata.artwork (WebIDL attribute) §: Defined in Media Session
MediaMetadataInit.artwork (WebIDL dictionary member) §: Defined in Media Session
as (markup attribute for link ) §: Defined in HTML; Referenced in HTML Accessibility API Mappings 1.0
HTMLLinkElement.as (WebIDL attribute) §: Defined in HTML
as a body (concept for byte sequence ) §: Defined in Fetch; Referenced in HTML, WebDriver BiDi
ascent-override (CSS descriptor for @font-face ) §: Defined in CSS Fonts 4 , CSS Fonts 5
CSSFontFaceDescriptors.ascent-override (WebIDL attribute) §: Defined in CSS Fonts 4
CSSFontFaceDescriptors.ascentOverride (WebIDL attribute) §: Defined in CSS Fonts 4
FontFace.ascentOverride (WebIDL attribute) §: Defined in CSS Font Loading 3
FontFaceDescriptors.ascentOverride (WebIDL dictionary member) §: Defined in CSS Font Loading 3
ASCII alpha (concept) §: Defined in Infra; Referenced in HTML, URL, User-Agent Client Hints
ASCII alphanumeric (concept) §: Defined in Infra; Referenced in HTML, MIME Sniffing, URL, Web NFC API, WebDriver BiDi, File System Access
ASCII byte (concept) §: Defined in Infra; Referenced in Encoding, URL, Protected Audience, User-Agent Client Hints, Loading Signed Exchanges
ASCII case-insensitive (concept) §: Defined in Infra; Referenced in DOM, CSS Variables 2, Encoding, Fetch, HTML, MIME Sniffing, URL, execCommand, Web Share Target API, Fenced Frame, Isolated Contexts, Speculation Rules, Credential Management 1, Content Security Policy: Embedded Enforcement, Content Security Policy 3, CSS Color 3, CSS Color 4, CSS Conditional 3, CSS Counter Styles 3, CSS Fonts 4, CSS Properties and Values API 1, CSS Syntax 3, CSS Typed OM 1, CSS Values 3, CSS Values 4, CSS Variables 1, CSS Will Change 1, ARIA in HTML, Internationalization Glossary, MathML Core, MathML 4.0, Media Queries 3, Media Queries 4, Media Queries 5, Media Session, Payment Method Manifest, Permissions Policy, Publication Manifest, Selection API, Selectors 4, Service Workers, WebRTC 1.0, WebTransport, XMLHttpRequest
ASCII case-insensitive (concept) §: Defined in Internationalization Glossary
ASCII code point (concept) §: Defined in Infra; Referenced in Encoding, URL, URL Pattern, Shared Storage API, Protected Audience
ASCII decode (concept) §: Defined in Infra; Referenced in Web NFC API, Loading Signed Exchanges
ASCII digit (concept) §: Defined in Infra; Referenced in Fetch, HTML, URL, URL Pattern, WebDriver BiDi, Storage Buckets API, Protected Audience, Content Security Policy 3
ASCII encode (concept) §: Defined in Infra; Referenced in Protected Audience, Loading Signed Exchanges
ASCII hex digit (concept) §: Defined in Infra; Referenced in HTML, URL, URL Pattern, Web NFC API, Attribution Reporting
ASCII lower alpha (concept) §: Defined in Infra; Referenced in HTML, Storage Buckets API, Protected Audience
ASCII lower hex digit (concept) §: Defined in Infra; Referenced in HTML, Web Bluetooth, Protected Audience, CSS Color 4, Web Cryptography API
ASCII lowercase (concept) §: Defined in Infra; Referenced in DOM, CSS Color HDR 1, Encoding, HTML, MIME Sniffing, URL, URL Pattern, Web Share Target API, WebDriver BiDi, Attribution Reporting, Content Security Policy 3, CSS Color 4, CSS Typed OM 1, CSSOM, File API, ARIA in HTML, MathML Core, Permissions, Trusted Types, WebDriver
ASCII string (concept) §: Defined in Infra; Referenced in Fetch, HTML, MIME Sniffing, Storage, URL, URL Pattern, No-Vary-Search, URL Fragment Text Directives, Shared Storage API, Loading Signed Exchanges, Content Security Policy 3
ASCII tab or newline (concept) §: Defined in Infra; Referenced in HTML, URL
ASCII upper alpha (concept) §: Defined in Infra; Referenced in HTML, Protected Audience, Loading Signed Exchanges
ASCII upper hex digit (concept) §: Defined in Infra; Referenced in HTML, URL
ASCII uppercase (concept) §: Defined in Infra; Referenced in DOM, HTML, Web Share Target API, CSSOM, Payment Request API
ASCII whitespace (concept) §: Defined in Infra; Referenced in DOM, Encoding, Fetch, HTML, MIME Sniffing, SMS One-Time Codes, Accessible Name and Description Computation 1.2, Content Security Policy 3, EPUB 3.3, WAI-ARIA, WAI-ARIA, WebVTT: The Web Video Text Tracks Format
aside (markup element) §: Defined in HTML; Referenced in HTML Accessibility API Mappings 1.0, ARIA in HTML, WAI-ARIA, WAI-ARIA
asin() (CSS function) §: Defined in CSS Values 4
Math.asin(x) (WebIDL operation) §: Defined in ECMAScript
Math.asinh(x) (WebIDL operation) §: Defined in ECMAScript
BigInt.asIntN(bits, bigint) (WebIDL operation) §: Defined in ECMAScript
ask the user to choose a Credential (algorithm) §: Defined in Credential Management 1
GPUImageCopyTexture.aspect (WebIDL dictionary member) §: Defined in WebGPU
GPUTextureViewDescriptor.aspect (WebIDL dictionary member) §: Defined in WebGPU
aspect-ratio (CSS descriptor for @container ) §: Defined in CSS Conditional 5
aspect-ratio (CSS property) §: Defined in CSS Sizing 4; Referenced in CSS Containment 1, CSS Containment 2, CSS Flexbox 1, CSS Grid Layout 1, CSS Grid Layout 2; Related terms: CSS value auto, CSS value auto && <ratio>
aspect-ratio (CSS descriptor for @media ) §: Defined in Media Queries 4 , Media Queries 5
aspectRatio (concept) §: Defined in Screen Capture
MediaTrackCapabilities.aspectRatio (WebIDL dictionary member) §: Defined in Media Capture and Streams
MediaTrackConstraintSet.aspectRatio (WebIDL dictionary member) §: Defined in Media Capture and Streams
MediaTrackSettings.aspectRatio (WebIDL dictionary member) §: Defined in Media Capture and Streams
MediaTrackSupportedConstraints.aspectRatio (WebIDL dictionary member) §: Defined in Media Capture and Streams
XRCylinderLayer.aspectRatio (WebIDL attribute) §: Defined in WebXR Layers API 1
XRCylinderLayerInit.aspectRatio (WebIDL dictionary member) §: Defined in WebXR Layers API 1
XRMediaCylinderLayerInit.aspectRatio (WebIDL dictionary member) §: Defined in WebXR Layers API 1
assemble primitives (algorithm) §: Defined in WebGPU
Assert (concept) §: Defined in Infra; Referenced in Fetch, File System, HTML, Private Aggregation API, Topics API, Navigational-Tracking Mitigations, The Storage Access API, URL, URL Pattern, WebDriver BiDi, Web IDL, Attribution Reporting, Fenced Frame, Prefetch, Prerendering Revamped, Speculation Rules, Observable, Measure Memory API, Web Periodic Background Synchronization, Portals, Private Network Access, HTML Sanitizer API, URL Fragment Text Directives, Shared Storage API, Private State Token API, Protected Audience, User-Agent Client Hints, Web App Launch Handler API, Web Smart Card API, WebUSB API, Compute Pressure 1, CSS Spatial Navigation 1, CSS View Transitions 1, CSS View Transitions 2, EditContext API, File API, Generic Sensor API, Geolocation, High Resolution Time, Indexed DB 3.0, MathML Core, Payment Request API, Referrer Policy, Screen Orientation, Trusted Types, Web Locks API, Web Share API, WebGPU, Web Neural Network API
console.assert(condition, ...data) (WebIDL operation) §: Defined in Console
RTCIdentityAssertionResult.assertion (WebIDL dictionary member) §: Defined in Identity for WebRTC 1.0
HTMLSlotElement.assign(...nodes) (WebIDL operation) §: Defined in HTML
Object.assign(target, ...sources) (WebIDL operation) §: Defined in ECMAScript
Location.assign(url) (WebIDL operation) §: Defined in HTML
assigned (concept for slottable ) §: Defined in DOM
assigned nodes (concept for slot ) §: Defined in DOM; Referenced in HTML, Accessible Name and Description Computation 1.2
assigned slot (concept for slottable ) §: Defined in DOM; Referenced in HTML
HTMLSlotElement.assignedElements(options) (WebIDL operation) §: Defined in HTML
HTMLSlotElement.assignedNodes(options) (WebIDL operation) §: Defined in HTML
AssignedNodesOptions (WebIDL dictionary) §: Defined in HTML; see also WebIDLPedia
Slottable.assignedSlot (WebIDL attribute) §: Defined in DOM
Assistive Technologies (concept) §: Defined in WAI-ARIA , WAI-ARIA
associated CSS style sheet (concept) §: Defined in CSSOM
associated Document (concept) §: Defined in HTML; Referenced in Compatibility, DOM, Fetch, Private Aggregation API, Navigational-Tracking Mitigations, requestStorageAccessFor API, Extending Storage Access API to non-cookie storage, Storage, The Capture-Handle Actions Mechanism, WebDriver BiDi, Web Bluetooth, Web Bluetooth Scanning, Digital Credentials, Direct Sockets API, Document Picture-in-Picture, Fenced Frame, Idle Detection API, Local Font Access, Prerendering Revamped, Observable, Web Serial API, Shared Storage API, Soft Navigations, Protected Audience, Web Preferences API, Web Smart Card API, WebHID API, WebUSB API, Badging API, Battery Status API, Compute Pressure 1, Credential Management 1, Content Security Policy 3, CSS Custom Highlight API 1, CSS Properties and Values API 1, CSS View Transitions 1, CSSOM, CSSOM View, Device Posture API, Encrypted Media Extensions, Event Timing API, Federated Credential Management API, Gamepad, Geolocation, Media Capture and Streams, Viewport Capture,