package js.html

The AbortController interface represents a controller object that allows you to abort one or more DOM requests as and when desired.

The AbortSignal interface represents a signal object that allows you to communicate with a DOM request (such as a Fetch) and abort it if required via an AbortController object.

The HTMLAnchorElement interface represents hyperlink elements and provides special properties and methods (beyond those of the regular HTMLElement object interface that they inherit from) for manipulating the layout and presentation of such elements.

The Animation interface of the Web Animations API represents a single animation player and provides playback controls and a timeline for an animation node or source.

The AnimationEffect interface of the Web Animations API defines current and future animation effects like KeyframeEffect, which can be passed to Animation objects for playing, and KeyframeEffectReadOnly (which is used by CSS Animations and Transitions).

The AnimationEvent interface represents events providing information related to animations.

The AnimationPlaybackEvent interface of the Web Animations API represents animation events.

The AnimationTimeline interface of the Web Animations API represents the timeline of an animation. This interface exists to define timeline features (inherited by DocumentTimeline and future timeline types) and is not itself directly used by developers. Anywhere you see AnimationTimeline, you should use DocumentTimeline or any other timeline type instead.

The HTMLAreaElement interface provides special properties and methods (beyond those of the regular object HTMLElement interface it also has available to it by inheritance) for manipulating the layout and presentation of area elements.

This type represents a DOM element's attribute as an object. In most DOM methods, you will probably directly retrieve the attribute as a string (e.g., Element.getAttribute(), but certain functions (e.g., Element.getAttributeNode()) or means of iterating give Attr types.

The HTMLAudioElement interface provides access to the properties of audio elements, as well as methods to manipulate them. It derives from the HTMLMediaElement interface.

The AudioTrack interface represents a single audio track from one of the HTML media elements, audio or video.

The AudioTrackList interface is used to represent a list of the audio tracks contained within a given HTML media element, with each track represented by a separate AudioTrack object in the list.

The HTMLBRElement interface represents a HTML line break element (br). It inherits from HTMLElement.

The HTMLBaseElement interface contains the base URI for a document. This object inherits all of the properties and methods as described in the HTMLElement interface.

The BatteryManager interface provides ways to get information about the system's battery charge level.

The beforeunload event is fired when the window, the document and its resources are about to be unloaded.

A Blob object represents a file-like object of immutable, raw data. Blobs represent data that isn't necessarily in a JavaScript-native format. The File interface is based on Blob, inheriting blob functionality and expanding it to support files on the user's system.

The BlobEvent interface represents events associated with a Blob. These blobs are typically, but not necessarily,  associated with media content.

The HTMLBodyElement interface provides special properties (beyond those of the regular HTMLElement interface they also inherit) for manipulating body elements.

The BroadcastChannel interface represents a named channel that any browsing context of a given origin can subscribe to. It allows communication between different documents (in different windows, tabs, frames or iframes) of the same origin. Messages are broadcasted via a message event fired at all BroadcastChannel objects listening to the channel.

The HTMLButtonElement interface provides properties and methods (beyond the button object interface it also has available to them by inheritance) for manipulating the layout and presentation of button elements.

The CDATASection interface represents a CDATA section that can be used within XML to include extended portions of unescaped text. The symbols and & don’t need escaping as they normally do when inside a CDATA section.

The CSS interface holds useful CSS-related methods. No object with this interface are implemented: it contains only static methods and therefore is a utilitarian interface.

An object implementing the CSSConditionRule interface represents a single condition CSS at-rule, which consists of a condition and a statement block. It is a child of CSSGroupingRule.

The CSSCounterStyleRule interface represents an @counter-style at-rule.

An object implementing the CSSGroupingRule interface represents any CSS at-rule that contains other rules nested within it.

The CSSKeyframeRule interface describes an object representing a set of style for a given keyframe. It corresponds to the contains of a single keyframe of a @keyframes at-rule. It implements the CSSRule interface with a type value of 8 (CSSRule.KEYFRAME_RULE).

The CSSKeyframesRule interface describes an object representing a complete set of keyframes for a CSS animation. It corresponds to the contains of a whole @keyframes at-rule. It implements the CSSRule interface with a type value of 7 (CSSRule.KEYFRAMES_RULE).

The CSSMediaRule is an interface representing a single CSS @media rule. It implements the CSSConditionRule interface, and therefore the CSSGroupingRule and the CSSRule interface with a type value of 4 (CSSRule.MEDIA_RULE).

The CSSNamespaceRule interface describes an object representing a single CSS @namespace at-rule. It implements the CSSRule interface, with a type value of 10 (CSSRule.NAMESPACE_RULE).

CSSPageRule is an interface representing a single CSS @page rule. It implements the CSSRule interface with a type value of 6 (CSSRule.PAGE_RULE).

The CSSRule interface represents a single CSS rule. There are several types of rules, listed in the Type constants section below.

A CSSRuleList is an (indirect-modify only) array-like object containing an ordered collection of CSSRule objects.

CSSStyleDeclaration represents a collection of CSS property-value pairs. It is used in a few APIs:

CSSStyleRule represents a single CSS style rule. It implements the CSSRule interface with a type value of 1 (CSSRule.STYLE_RULE).

The CSSStyleSheet interface represents a single CSS style sheet. It inherits properties and methods from its parent, StyleSheet.

The CSSSupportsRule interface describes an object representing a single CSS @supports at-rule. It implements the CSSConditionRule interface, and therefore the CSSRule and CSSGroupingRule interfaces with a type value of 12 (CSSRule.SUPPORTS_RULE).

The Cache interface provides a storage mechanism for Request / Response object pairs that are cached, for example as part of the ServiceWorker life cycle. Note that the Cache interface is exposed to windowed scopes as well as workers. You don't have to use it in conjunction with service workers, even though it is defined in the service worker spec.

The CacheStorage interface represents the storage for Cache objects.

The HTMLCanvasElement interface provides properties and methods for manipulating the layout and presentation of canvas elements. The HTMLCanvasElement interface also inherits the properties and methods of the HTMLElement interface.

The CanvasGradient interface represents an opaque object describing a gradient. It is returned by the methods CanvasRenderingContext2D.createLinearGradient() or CanvasRenderingContext2D.createRadialGradient().

The CanvasPattern interface represents an opaque object describing a pattern, based on an image, a canvas, or a video, created by the CanvasRenderingContext2D.createPattern() method.

To get an object of this interface, call getContext() on a canvas element, supplying "2d" as the argument:

The CaretPosition interface represents the caret postion, an indicator for the text insertion point. You can get a CaretPosition using the document.caretPositionFromPoint method.

The CharacterData abstract interface represents a Node object that contains characters. This is an abstract interface, meaning there aren't any object of type CharacterData: it is implemented by other interfaces, like Text, '. In XML, the character sequence '--' cannot be used within a comment.">Comment, or ProcessingInstruction which aren't abstract.

The Client interface represents an executable context such as a Worker, or a SharedWorker. Window clients are represented by the more-specific WindowClient. You can get Client/WindowClient objects from methods such as Clients.matchAll() and Clients.get().

The Clients interface provides access to Client objects. Access it via self.clients within a service worker.

The Clipboard interface implements the Clipboard API, providing—if the user grants permission—both read and write access to the contents of the system clipboard.

The ClipboardEvent interface represents events providing information related to modification of the clipboard, that is cut, copy, and paste events.

A CloseEvent is sent to clients using WebSockets when the connection is closed. This is delivered to the listener indicated by the WebSocket object's onclose attribute.

The Comment interface represents textual notations within markup; although it is generally not visually shown, such comments are available to be read in the source view. Comments are represented in HTML and XML as content between '!--' and '--'. In XML, the character sequence '--' cannot be used within a comment.

The DOM CompositionEvent represents events that occur due to the user indirectly entering text.

The Console object provides access to the browser's debugging console (e.g. the Web Console in Firefox). The specifics of how it works varies from browser to browser, but there is a de facto set of features that are typically provided.

The Console object provides access to the browser's debugging console (e.g. the Web Console in Firefox). The specifics of how it works varies from browser to browser, but there is a de facto set of features that are typically provided.

The Crypto interface represents basic cryptography features available in the current context. It allows access to a cryptographically strong random number generator and to cryptographic primitives.

The CryptoKey interface represents a cryptographic key derived from a specific key algorithm.

This interface inherits properties from its parent, Event:

The HTMLDListElement interface provides special properties (beyond those of the regular HTMLElement interface it also has available to it by inheritance) for manipulating definition list elements.

Element is the most general base class from which all objects in a Document inherit. It only has methods and properties common to all kinds of elements. More specific classes inherit from Element.

The DOMError interface describes an error object that contains an error name.

The DOMException interface represents an abnormal event (called an exception) which occurs as a result of calling a method or accessing a property of a web API.

The DOMImplementation interface represent an object providing methods which are not dependent on any particular document. Such an object is returned by the Document.implementation property.

The DOMMatrix interface represents 4x4 matrices, suitable for 2D and 3D operations.

The DOMMatrixReadOnly interface represents 4x4 matrices, suitable for 2D and 3D operations. If this interface defines only read-only matrices, the DOMMatrix interface which inherits from it, add all the properties and the methods to allow to have modifiable matrices.

The DOMParser interface provides the ability to parse XML or HTML source code from a string into a DOM Document.

A DOMPoint object represents a 2D or 3D point in a coordinate system; it includes values for the coordinates in up to three dimensions, as well as an optional perspective value.

The DOMPointReadOnly interface specifies the coordinate and perspective fields used by DOMPoint to define a 2D or 3D point in a coordinate system.

A DOMQuad is a collection of four DOMPoints defining the corners of an arbitrary quadrilateral. Returning DOMQuads lets getBoxQuads() return accurate information even when arbitrary 2D or 3D transforms are present. It has a handy bounds attribute returning a DOMRectReadOnly for those cases where you just want an axis-aligned bounding rectangle.

A DOMRect represents a rectangle.

The DOMRectReadOnly interface specifies the standard properties used by DOMRect to define a rectangle.

A type returned by some APIs which contains a list of DOMString (strings).

Used by the dataset HTML attribute to represent data for custom attributes added to elements.

The DOMTokenList interface represents a set of space-separated tokens. Such a set is returned by Element.classList, HTMLLinkElement.relList, HTMLAnchorElement.relList, HTMLAreaElement.relList, HTMLIframeElement.sandbox, or HTMLOutputElement.htmlFor. It is indexed beginning with 0 as with JavaScript Array objects. DOMTokenList is always case-sensitive.

The HTMLDataElement interface provides special properties (beyond the regular HTMLElement interface it also has available to it by inheritance) for manipulating data elements.

The HTMLDataListElement interface provides special properties (beyond the HTMLElement object interface it also has available to it by inheritance) to manipulate datalist elements and their content.

The DataTransfer object is used to hold the data that is being dragged during a drag and drop operation. It may hold one or more data items, each of one or more data types. For more information about drag and drop, see HTML Drag and Drop API.

The DataTransferItem object represents one drag data item. During a drag operation, each drag event has a dataTransfer property which contains a list of drag data items. Each item in the list is a DataTransferItem object.

The DataTransferItemList object is a list of DataTransferItem objects representing items being dragged. During a drag operation, each DragEvent has a dataTransfer property and that property is a DataTransferItemList.

The DedicatedWorkerGlobalScope object (the Worker global scope) is accessible through the self keyword. Some additional global functions, namespaces objects, and constructors, not typically associated with the worker global scope, but available on it, are listed in the JavaScript Reference. See also: Functions available to workers.

The HTMLDetailsElement interface provides special properties (beyond the regular HTMLElement interface it also has available to it by inheritance) for manipulating details elements.

The DeviceMotionEvent provides web developers with information about the speed of changes for the device's position and orientation.

The DeviceOrientationEvent provides web developers with information from the physical orientation of the device running the web page.

The HTMLDivElement interface provides special properties (beyond the regular HTMLElement interface it also has available to it by inheritance) for manipulating div elements.

The Document interface represents any web page loaded in the browser and serves as an entry point into the web page's content, which is the DOM tree.HTMLElement

The DocumentFragment interface represents a minimal document object that has no parent. It is used as a lightweight version of Document that stores a segment of a document structure comprised of nodes just like a standard document. The key difference is that because the document fragment isn't part of the active document tree structure, changes made to the fragment don't affect the document, cause reflow, or incur any performance impact that can occur when changes are made.

The DocumentTimeline interface of the the Web Animations API represents animation timelines, including the default document timeline (accessed via Document.timeline).

The DocumentType interface represents a Node containing a doctype.

The DragEvent interface is a DOM event that represents a drag and drop interaction. The user initiates a drag by placing a pointer device (such as a mouse) on the touch surface and then dragging the pointer to a new location (such as another DOM element). Applications are free to interpret a drag and drop interaction in an application-specific way.

The HTMLElement interface represents any HTML element. Some elements directly implement this interface, others implement it via an interface that inherits it.

The HTMLEmbedElement interface, which provides special properties (beyond the regular HTMLElement interface it also has available to it by inheritance) for manipulating embed elements.

The ErrorEvent interface represents events providing information related to errors in scripts or in files.

The Event interface represents any event which takes place in the DOM; some are user-generated (such as mouse or keyboard events), while others are generated by APIs (such as events that indicate an animation has finished running, a video has been paused, and so forth). There are many types of events, some of which use other interfaces based on the main Event interface. Event itself contains the properties and methods which are common to all events.

The EventSource interface is web content's interface to server-sent events. An EventSource instance opens a persistent connection to an HTTP server, which sends events in text/event-stream format.

EventTarget is an interface implemented by objects that can receive events and may have listeners for them.

The ExtendableEvent interface extends the lifetime of the install and activate events dispatched on the global scope as part of the service worker lifecycle. This ensures that any functional events (like FetchEvent) are not dispatched until it upgrades database schemas and deletes the outdated cache entries.

The ExtendableMessageEvent interface of the ServiceWorker API represents the event object of a message event fired on a service worker (when a channel message is received on the ServiceWorkerGlobalScope from another context) — extends the lifetime of such events.

This is the event type for fetch events dispatched on the service worker global scope. It contains information about the fetch, including the request and how the receiver will treat the response. It provides the event.respondWith() method, which allows us to provide a response to this fetch.

The HTMLFieldSetElement interface has special properties and methods (beyond the regular HTMLElement interface it also has available to it by inheritance) for manipulating the layout and presentation of field-set elements.

The File interface provides information about files and allows JavaScript in a web page to access their content.

An object of this type is returned by the files property of the HTML input element; this lets you access the list of files selected with the input type="file" element. It's also used for a list of files dropped into web content when using the drag and drop API; see the DataTransfer object for details on this usage.

The FileReader object lets web applications asynchronously read the contents of files (or raw data buffers) stored on the user's computer, using File or Blob objects to specify the file or data to read.

The FileReaderSync interface allows to read File or Blob objects in a synchronous way.

The File and Directory Entries API interface FileSystem is used to represent a file system. These objects can be obtained from the filesystem property on any file system entry. Some browsers offer additional APIs to create and manage file systems, such as Chrome's requestFileSystem() method.

The FileSystemDirectoryEntry interface of the File and Directory Entries API represents a directory in a file system. It provides methods which make it possible to access and manipulate the files in a directory, as well as to access the entries within the directory.

The FileSystemDirectoryReader interface of the File and Directory Entries API lets you access the FileEntry-based objects (generally FileSystemFileEntry or FileSystemDirectoryEntry) representing each entry in a directory.

The FileSystemEntry interface of the File and Directory Entries API represents a single in a file system. The entry can be a file or a directory (directories are represented by the DirectoryEntry interface). It includes methods for working with files—including copying, moving, removing, and reading files—as well as information about a file it points to—including the file name and its path from the root to the entry.

The FileSystemFileEntry interface of the File System API represents a file in a file system. It offers properties describing the file's attributes, as well as the file() method, which creates a File object that can be used to read the file.

The FocusEvent interface represents focus-related events like focus, blur, focusin, or focusout.

Implements the document object model (DOM) representation of the font element. The HTML Font Element font defines the font size, font face and color of text.

The FontFace interface represents a single usable font face. It allows control of the source of the font face, being a URL to an external resource, or a buffer; it also allows control of when the font face is loaded and its current status.

The FontFaceSet interface of the CSS Font Loading API manages the loading of font-faces and querying of their download status.

The FontFaceSetLoadEvent interface of the the Css Font Loading API is fired whenever a FontFaceSet loads.

The FormData interface provides a way to easily construct a set of key/value pairs representing form fields and their values, which can then be easily sent using the XMLHttpRequest.send() method. It uses the same format a form would use if the encoding type were set to "multipart/form-data".

The HTMLFormElement interface represents a form element in the DOM; it allows access to and in some cases modification of aspects of the form, as well as access to its component elements.

The HTMLFrameSetElement interface provides special properties (beyond those of the regular HTMLElement interface they also inherit) for manipulating frameset elements.

The Gamepad interface of the Gamepad API defines an individual gamepad or other controller, allowing access to information such as button presses, axis positions, and id.

The GamepadButton interface defines an individual button of a gamepad or other controller, allowing access to the current state of different types of buttons available on the control device.

The GamepadEvent interface of the Gamepad API contains references to gamepads connected to the system, which is what the gamepad events Window.gamepadconnected and Window.gamepaddisconnected are fired in response to.

The HTMLHRElement interface provides special properties (beyond those of the HTMLElement interface it also has available to it by inheritance) for manipulating hr elements.

The HTMLCollection interface represents a generic collection (array-like object similar to arguments) of elements (in document order) and offers methods and properties for selecting from the list.

HTMLDocument is an abstract interface which extends the Document interface to add HTML-specific features to the document object. It represents the root of the HTML document, within which its entire DOM hierarchy resides.

The HTMLFormControlsCollection interface represents a collection of HTML form control elements.

HTMLOptionsCollection is an interface representing a collection of HTML option elements (in document order) and offers methods and properties for traversing the list as well as optionally altering its items. This type is returned solely by the "options" property of select.

The HashChangeEvent event is fired when the fragment identifier of the URL has changed (the part of the URL that follows the # symbol, including the # symbol).

The HTMLHeadElement interface contains the descriptive information, or metadata, for a document. This object inherits all of the properties and methods described in the HTMLElement interface.

The Headers interface of the Fetch API allows you to perform various actions on HTTP request and response headers. These actions include retrieving, setting, adding to, and removing. A Headers object has an associated header list, which is initially empty and consists of zero or more name and value pairs.  You can add to this using methods like append() (see Examples.) In all methods of this interface, header names are matched by case-insensitive byte sequence.

The HTMLHeadingElement interface represents the different heading elements. It inherits methods and properties from the HTMLElement interface.

The History interface allows manipulation of the browser session history, that is the pages visited in the tab or frame that the current page is loaded in.

The HTMLHtmlElement interface serves as the root node for a given HTML document.  This object inherits the properties and methods described in the HTMLElement interface.

The HTMLIFrameElement interface provides special properties and methods (beyond those of the HTMLElement interface it also has available to it by inheritance) for manipulating the layout and presentation of inline frame elements.

The ImageBitmap interface represents a bitmap image which can be drawn to a canvas without undue latency. It can be created from a variety of source objects using the createImageBitmap() factory method. ImageBitmap provides an asynchronous and resource efficient pathway to prepare textures for rendering in WebGL.

The ImageBitmapRenderingContext interface is a canvas rendering context which only provides the functionality to replace the canvas's contents with the given ImageBitmap. Its context id (the first argument to HTMLCanvasElement.getContext() or OffscreenCanvas.getContext()  is "bitmaprenderer".

The ImageCapture interface of the MediaStream Image Capture API provides an interface for capturing images from a photographic device referenced through a valid MediaStreamTrack.

The ImageData interface represents the underlying pixel data of an area of a canvas element. It is created using the ImageData() constructor or creator methods on the CanvasRenderingContext2D object associated with a canvas: createImageData() and getImageData(). It can also be used to set a part of the canvas by using putImageData().

The HTMLImageElement interface provides special properties and methods  for manipulating the layout and presentation of img elements.

The HTMLInputElement interface provides special properties and methods for manipulating the layout and presentation of input elements.

The InputEvent interface represents an event notifying of editable content change.

provides a way to asynchronously observe changes in the intersection of a target element with an ancestor element or with a top-level document's viewport.

The IntersectionObserverEntry interface of the Intersection Observer API describes the intersection between the target element and its root container at a specific moment of transition.

KeyboardEvent objects describe a user interaction with the keyboard; each event describes a single interaction between the user and a key (or combination of a key with modifier keys) on the keyboard.

The KeyframeEffect interface of the Web Animations API lets us create sets of animatable properties and values, called keyframes. These can then be played using the Animation() constructor.

The HTMLLIElement interface exposes specific properties and methods (beyond those defined by regular HTMLElement interface it also has available to it by inheritance) for manipulating list elements.

The HTMLLabelElement interface gives access to properties specific to label elements. It inherits methods and properties from the base HTMLElement interface.

The HTMLLegendElement is an interface allowing to access properties of the legend elements. It inherits properties and methods from the HTMLElement interface.

The HTMLLinkElement interface represents reference information for external resources and the relationship of those resources to a document and vice-versa. This object inherits all of the properties and methods of the HTMLElement interface.

The LocalMediaStream interface was part of the Media Capture and Streams API, representing a stream of data being generated locally (such as by getUserMedia(). However, getUserMedia() now returns a MediaStream instead, and this interface has been removed from the specification.

The Location interface represents the location (URL) of the object it is linked to. Changes done on it are reflected on the object it relates to. Both the Document and Window interface have such a linked Location, accessible via Document.location and Window.location respectively.

The HTMLMapElement interface provides special properties and methods (beyond those of the regular object HTMLElement interface it also has available to it by inheritance) for manipulating the layout and presentation of map elements.

The MediaDevicesInfo interface contains information that describes a single media input or output device.

The MediaDevices interface provides access to connected media input devices like cameras and microphones, as well as screen sharing. In essence, it lets you obtain access to any hardware source of media data.

The HTMLMediaElement interface adds to HTMLElement the properties and methods needed to support basic media-related capabilities that are common to audio and video.

The MediaError interface represents an error which occurred while handling media in an HTML media element based on HTMLMediaElement, such as audio or video.

A MediaQueryList object stores information on a media query applied to a document, and handles sending notifications to listeners when the media query state change (i.e. when the media query test starts or stops evaluating to true).

The MediaQueryListEvent object stores information on the changes that have happened to a MediaQueryList object — instances are available as the event object on a function referenced by a MediaQueryList.onchange property or MediaQueryList.addEvent() call.

The MediaRecorder interface of the MediaStream Recording API provides functionality to easily record media. It is created using the MediaRecorder() constructor.

The MediaRecorderErrorEvent interface represents errors returned by the MediaStream Recording API. It is an Event object that encapsulates a reference to a DOMException describing the error that occurred.

The MediaSource interface of the Media Source Extensions API represents a source of media data for an HTMLMediaElement object. A MediaSource object can be attached to a HTMLMediaElement to be played in the user agent.

The MediaStream interface represents a stream of media content. A stream consists of several tracks such as video or audio tracks. Each track is specified as an instance of MediaStreamTrack.

The MediaStreamEvent interface represents events that occurs in relation to a MediaStream. Two events of this type can be thrown: addstream and removestream.

The MediaStreamTrack interface represents a single media track within a stream; typically, these are audio or video tracks, but other track types may exist as well.

The MediaStreamTrackEvent interface represents events which indicate that a MediaStream has had tracks added to or removed from the stream through calls to Media Stream API methods. These events are sent to the stream when these changes occur.

The MessageChannel interface of the Channel Messaging API allows us to create a new message channel and send data through it via its two MessagePort properties.

The MessageEvent interface represents a message received by a target object.

The MessagePort interface of the Channel Messaging API represents one of the two ports of a MessageChannel, allowing messages to be sent from one port and listening out for them arriving at the other.

The HTMLMetaElement interface contains descriptive metadata about a document. It inherits all of the properties and methods described in the HTMLElement interface.

The HTML meter elements expose the HTMLMeterElement interface, which provides special properties and methods (beyond the HTMLElement object interface they also have available to them by inheritance) for manipulating the layout and presentation of meter elements.

The MimeType interface provides contains information about a MIME type associated with a particular plugin. NavigatorPlugins.mimeTypes returns an array of this object.

The MimeTypeArray interface returns an array of MimeType instances, each of which contains information about a supported browser plugins. This object is returned by NavigatorPlugins.mimeTypes.

The HTMLModElement interface provides special properties (beyond the regular methods and properties available through the HTMLElement interface they also have available to them by inheritance) for manipulating modification elements, that is del and ins.

The MouseEvent interface represents events that occur due to the user interacting with a pointing device (such as a mouse). Common events using this interface include click, dblclick, mouseup, mousedown.

The MouseScrollEvent interface represents events that occur due to the user moving a mouse wheel or similar input device.

Provides event properties that are specific to modifications to the Document Object Model (DOM) hierarchy and nodes.

The MutationObserver interface provides the ability to watch for changes being made to the DOM tree. It is designed as a replacement for the older Mutation Events feature which was part of the DOM3 Events specification.

A MutationRecord represents an individual DOM mutation. It is the object that is passed to MutationObserver's callback.

The NamedNodeMap interface represents a collection of Attr objects. Objects inside a NamedNodeMap are not in any particular order, unlike NodeList, although they may be accessed by an index as in an array.

The Navigator interface represents the state and the identity of the user agent. It allows scripts to query it and to register themselves to carry on some activities.

Node is an interface from which a number of DOM API object types inherit. It allows those types to be treated similarly; for example, inheriting the same set of methods, or being tested in the same way.

A NodeFilter interface represents an object used to filter the nodes in a NodeIterator or TreeWalker. They don't know anything about the DOM or how to traverse nodes; they just know how to evaluate a single node against the provided filter.

The NodeIterator interface represents an iterator over the members of a list of the nodes in a subtree of the DOM. The nodes will be returned in document order.

NodeList objects are collections of nodes such as those returned by properties such as Node.childNodes and the document.querySelectorAll() method.

The Notification interface of the Notifications API is used to configure and display desktop notifications to the user.

The parameter passed into the onnotificationclick handler, the NotificationEvent interface represents a notification click event that is dispatched on the ServiceWorkerGlobalScope of a ServiceWorker.

The HTMLOListElement interface provides special properties (beyond those defined on the regular HTMLElement interface it also has available to it by inheritance) for manipulating ordered list elements.

The HTMLObjectElement interface provides special properties and methods (beyond those on the HTMLElement interface it also has available to it by inheritance) for manipulating the layout and presentation of object element, representing external resources.

The HTMLOptGroupElement interface provides special properties and methods (beyond the regular HTMLElement object interface they also have available to them by inheritance) for manipulating the layout and presentation of optgroup elements.

The HTMLOptionElement interface represents option elements and inherits all classes and methods of the HTMLElement interface.

The HTMLOutputElement interface provides properties and methods (beyond those inherited from HTMLElement) for manipulating the layout and presentation of output elements.

The PageTransitionEvent is fired when a document is being loaded or unloaded.

The HTMLParagraphElement interface provides special properties (beyond those of the regular HTMLElement object interface it inherits) for manipulating p elements.

The HTMLParamElement interface provides special properties (beyond those of the regular HTMLElement object interface it inherits) for manipulating param elements, representing a pair of a key and a value that acts as a parameter for an object element.

The Path2D interface of the Canvas 2D API is used to declare paths that are then later used on CanvasRenderingContext2D objects. The path methods of the CanvasRenderingContext2D interface are present on this interface as well and are allowing you to create paths that you can retain and replay as required on a canvas.

The Performance interface provides access to performance-related information for the current page. It's part of the High Resolution Time API, but is enhanced by the Performance Timeline API, the Navigation Timing API, the User Timing API, and the Resource Timing API.

The PerformanceEntry object encapsulates a single performance metric that is part of the performance timeline. A performance entry can be directly created by making a performance mark or measure (for example by calling the mark() method) at an explicit point in an application. Performance entries are also created in indirect ways such as loading a resource (such as an image).

PerformanceMark is an abstract interface for PerformanceEntry objects with an entryType of "mark". Entries of this type are created by calling performance.mark() to add a named DOMHighResTimeStamp (the mark) to the browser's performance timeline.

PerformanceMeasure is an abstract interface for PerformanceEntry objects with an entryType of "measure". Entries of this type are created by calling performance.measure() to add a named DOMHighResTimeStamp (the measure) between two marks to the browser's performance timeline.

The legacy PerformanceNavigation interface represents information about how the navigation to the current document was done.

The PerformanceNavigationTiming interface provides methods and properties to store and retrieve metrics regarding the browser's document navigation events. For example, this interface can be used to determine how much time it takes to load or unload a document.

The PerformanceObserver interface is used to observe performance measurement events and be notified of new performance entries as they are recorded in the browser's performance timeline.

The PerformanceObserverEntryList interface is a list of peformance events that were explicitly observed via the observe() method.

The PerformanceResourceTiming interface enables retrieval and analysis of detailed network timing data regarding the loading of an application's resources. An application can use the timing metrics to determine, for example, the length of time it takes to fetch a specific resource, such as an XMLHttpRequest, SVG, image, or script.

The PerformanceServerTiming interface surfaces server metrics that are sent with the response in the Server-Timing HTTP header.

The PerformanceTiming interface is a legacy interface kept for backwards compatibility and contains properties that offer performance timing information for various events which occur during the loading and use of the current page. You get a PerformanceTiming object describing your page using the window.performance.timing property.

The PermissionStatus interface of the Permissions API provides the state of an object and an event handler for monitoring changes to said state.

Documentation Permissions by Mozilla Contributors, licensed under CC-BY-SA 2.5.

The HTMLPictureElement interface represents a picture HTML element. It doesn't implement specific properties or methods.

The Plugin interface provides information about a browser plugin.

The PluginArray interface is used to store a list of Plugin objects describing the available plugins; it's returned by the window.navigator.plugins property. The PluginArray is not a JavaScript array, but has the length property and supports accessing individual items using bracket notation (plugins[2]), as well as via item(index) and namedItem("name") methods.

The PointerEvent interface represents the state of a DOM event produced by a pointer such as the geometry of the contact point, the device type that generated the event, the amount of pressure that was applied on the contact surface, etc.

An event handler for the popstate event on the window.

The PositionError interface represents the reason of an error occurring when using the geolocating device.

The HTMLPreElement interface expose specific properties and methods (beyond those defined by regular HTMLElement interface it also has available to it by inheritance) for manipulating block of preformatted text.

A processing instruction embeds application-specific instructions in XML which can be ignored by other applications that don't recognize them.

The HTMLProgressElement interface provides special properties and methods (beyond the regular HTMLElement interface it also has available to it by inheritance) for manipulating the layout and presentation of progress elements.

The ProgressEvent interface represents events measuring progress of an underlying process, like an HTTP request (for an XMLHttpRequest, or the loading of the underlying resource of an img, audio, video, style or link).

The HTMLQuoteElement interface provides special properties and methods (beyond the regular HTMLElement interface it also has available to it by inheritance) for manipulating quoting elements, like blockquote and q, but not the cite element.

The RadioNodeList interface represents a collection of elements in a form or a fieldset element.

The Range interface represents a fragment of a document that can contain nodes and parts of text nodes.

The Request interface of the Fetch API represents a resource request.

The Response interface of the Fetch API represents the response to a request.

The Screen interface represents a screen, usually the one on which the current window is being rendered, and is obtained using window.screen.

The ScreenOrientation interface of the the Screen Orientation API provides information about the current orientation of the document.

HTML script elements expose the HTMLScriptElement interface, which provides special properties and methods for manipulating the behavior and execution of script elements (beyond the inherited HTMLElement interface).

The SecurityPolicyViolationEvent interface inherits from Event, and represents the event object of an event sent on a document or worker when its content security policy is violated.

The HTMLSelectElement interface represents a select HTML Element. These elements also share all of the properties and methods of other HTML elements via the HTMLElement interface.

A Selection object represents the range of text selected by the user or the current position of the caret. To obtain a Selection object for examination or modification, call window.getSelection().

The ServiceWorker interface of the ServiceWorker API provides a reference to a service worker. Multiple browsing contexts (e.g. pages, workers, etc.) can be associated with the same service worker, each through a unique ServiceWorker object.

The ServiceWorkerContainer interface of the ServiceWorker API provides an object representing the service worker as an overall unit in the network ecosystem, including facilities to register, unregister and update service workers, and access the state of service workers and their registrations.

The ServiceWorkerGlobalScope interface of the ServiceWorker API represents the global execution context of a service worker.

The ServiceWorkerRegistration interface of the ServiceWorker API represents the service worker registration. You register a service worker to control one or more pages that share the same origin.

The ShadowRoot interface of the Shadow DOM API is the root node of a DOM subtree that is rendered separately from a document's main DOM tree.

The SharedWorker interface represents a specific kind of worker that can be accessed from several browsing contexts, such as several windows, iframes or even workers. They implement an interface different than dedicated workers and have a different global scope, SharedWorkerGlobalScope.

The SharedWorkerGlobalScope object (the SharedWorker global scope) is accessible through the self keyword. Some additional global functions, namespaces objects, and constructors, not typically associated with the worker global scope, but available on it, are listed in the JavaScript Reference. See the complete list of functions available to workers.

The HTMLSlotElement interface of the Shadow DOM API enables access to the name and assigned nodes of an HTML slot element.

The SourceBuffer interface represents a chunk of media to be passed into an HTMLMediaElement and played, via a MediaSource object. This can be made up of one or several media segments.

The SourceBufferList interface represents a simple container list for multiple SourceBuffer objects.

The HTMLSourceElement interface provides special properties (beyond the regular HTMLElement object interface it also has available to it by inheritance) for manipulating source elements.

The HTMLSpanElement interface represents a span element and derives from the HTMLElement interface, but without implementing any additional properties or methods.

The SpeechGrammar interface of the Web Speech API represents a set of words or patterns of words that we want the recognition service to recognize.

The SpeechGrammarList interface of the Web Speech API represents a list of SpeechGrammar objects containing words or patterns of words that we want the recognition service to recognize.

The SpeechRecognition interface of the Web Speech API is the controller interface for the recognition service; this also handles the SpeechRecognitionEvent sent from the recognition service.

The SpeechRecognitionAlternative interface of the Web Speech API represents a single word that has been recognised by the speech recognition service.

The SpeechRecognitionError interface of the Web Speech API represents error messages from the recognition service.

The SpeechRecognitionEvent interface of the Web Speech API represents the event object for the result and nomatch events, and contains all the data associated with an interim or final speech recognition result.

The SpeechRecognitionResult interface of the Web Speech API represents a single recognition match, which may contain multiple SpeechRecognitionAlternative objects.

The SpeechRecognitionResultList interface of the Web Speech API represents a list of SpeechRecognitionResult objects, or a single one if results are being captured in continuous mode.

The SpeechSynthesis interface of the Web Speech API is the controller interface for the speech service; this can be used to retrieve information about the synthesis voices available on the device, start and pause speech, and other commands besides.

The SpeechSynthesisErrorEvent interface of the Web Speech API contains information about any errors that occur while processing SpeechSynthesisUtterance objects in the speech service.

The SpeechSynthesisEvent interface of the Web Speech API contains information about the current state of SpeechSynthesisUtterance objects that have been processed in the speech service.

The SpeechSynthesisUtterance interface of the Web Speech API represents a speech request. It contains the content the speech service should read and information about how to read it (e.g. language, pitch and volume.)

The SpeechSynthesisVoice interface of the Web Speech API represents a voice that the system supports. Every SpeechSynthesisVoice has its own relative speech service including information about language, name and URI.

The Storage interface of the Web Storage API provides access to a particular domain's session or local storage. It allows, for example, the addition, modification, or deletion of stored data items.

A StorageEvent is sent to a window when a storage area it has access to is changed within the context of another document.

The StorageManager interface of the the Storage API provides an interface for managing persistance permissions and estimating available storage. You can get a reference to this interface using either navigator.storage or WorkerNavigator.storage.

The HTMLStyleElement interface represents a style element. It inherits properties and methods from its parent, HTMLElement, and from LinkStyle.

An object implementing the StyleSheet interface represents a single style sheet. CSS style sheets will further implement the more specialized CSSStyleSheet interface.

The StyleSheetList interface represents a list of StyleSheet.

The SubtleCrypto interface represents a set of cryptographic primitives. It is available via the Crypto.subtle properties available in a window context (via Window.crypto).

The HTMLTableCaptionElement interface special properties (beyond the regular HTMLElement interface it also has available to it by inheritance) for manipulating table caption elements.

The HTMLTableCellElement interface provides special properties and methods (beyond the regular HTMLElement interface it also has available to it by inheritance) for manipulating the layout and presentation of table cells, either header or data cells, in an HTML document.

The HTMLTableColElement interface provides special properties (beyond the HTMLElement interface it also has available to it inheritance) for manipulating single or grouped table column elements.

The HTMLTableElement interface provides special properties and methods (beyond the regular HTMLElement object interface it also has available to it by inheritance) for manipulating the layout and presentation of tables in an HTML document.

The HTMLTableRowElement interface provides special properties and methods (beyond the HTMLElement interface it also has available to it by inheritance) for manipulating the layout and presentation of rows in an HTML table.

The HTMLTableSectionElement interface provides special properties and methods (beyond the HTMLElement interface it also has available to it by inheritance) for manipulating the layout and presentation of sections, that is headers, footers and bodies, in an HTML table.

The HTMLTemplateElement interface enables access to the contents of an HTML template element.

The Text interface represents the textual content of Element or Attr.  If an element has no markup within its content, it has a single child implementing Text that contains the element's text.  However, if the element contains markup, it is parsed into information items and Text nodes that form its children.

The HTMLTextAreaElement interface provides special properties and methods for manipulating the layout and presentation of textarea elements.

The TextDecoder interface represents a decoder for a specific method, that is a specific character encoding, like utf-8, iso-8859-2, koi8, cp1261, gbk, etc. A decoder takes a stream of bytes as input and emits a stream of code points. For a more scalable, non-native library, see StringView – a C-like representation of strings based on typed arrays.

TextEncoder takes a stream of code points as input and emits a stream of bytes. For a more scalable, non-native library, see StringView – a C-like representation of strings based on typed arrays.

The TextMetrics interface represents the dimension of a text in the canvas, as created by the CanvasRenderingContext2D.measureText() method.

This interface also inherits properties from EventTarget.

The HTMLTimeElement interface provides special properties (beyond the regular HTMLElement interface it also has available to it by inheritance) for manipulating time elements.

Extends Event.

The TimeRanges interface is used to represent a set of time ranges, primarily for the purpose of tracking which portions of media have been buffered when loading it for use by the audio and video elements.

The HTMLTitleElement interface contains the title for a document. This element inherits all of the properties and methods of the HTMLElement interface.

The Touch interface represents a single contact point on a touch-sensitive device. The contact point is commonly a finger or stylus and the device may be a touchscreen or trackpad.

The TouchEvent interface represents an event sent when the state of contacts with a touch-sensitive surface changes. This surface can be a touch screen or trackpad, for example. The event can describe one or more points of contact with the screen and includes support for detecting movement, addition and removal of contact points, and so forth.

The TouchList interface represents a list of contact points with a touch surface; for example, if the user has three fingers on the touch surface (such as a screen or trackpad), the corresponding TouchList object would have one Touch object for each finger, for a total of three entries.

The HTMLTrackElement

The TransitionEvent interface represents events providing information related to transitions.

The TreeWalker object represents the nodes of a document subtree and a position within them.

The UIEvent interface represents simple user interface events.

The HTMLUListElement interface provides special properties (beyond those defined on the regular HTMLElement interface it also has available to it by inheritance) for manipulating unordered list elements.

The URL interface represents an object providing static methods used for creating object URLs.

The URLSearchParams interface defines utility methods to work with the query string of a URL.

The HTMLUnknownElement interface represents an invalid HTML element and derives from the HTMLElement interface, but without implementing any additional properties or methods.

VTTCues represent a cue in a text track.

The ValidityState interface represents the validity states that an element can be in, with respect to constraint validation. Together, they help explain why an element's value fails to validate, if it's not valid.

The HTMLVideoElement interface provides special properties and methods for manipulating video objects. It also inherits properties and methods of HTMLMediaElement and HTMLElement.

The VideoPlaybackQuality interface represents the set of metrics describing the playback quality of a video.

The VisualViewport interface of the the Visual Viewport API represents the visual viewport for a given window. For a page containing iframes, each iframe, as well as the containing page, will have a unique window object. Each window on a page will have a unique VisualViewport representing the properties associated with that window.

The WebSocket object provides the API for creating and managing a WebSocket connection to a server, as well as for sending and receiving data on the connection.

The WheelEvent interface represents events that occur due to the user moving a mouse wheel or similar input device.

The Window interface represents a window containing a DOM document; the document property points to the DOM document loaded in that window.

The WindowClient interface of the ServiceWorker API represents the scope of a service worker client that is a document in a browser context, controlled by an active worker. The service worker client independently selects and uses a service worker for its own loading and sub-resources.

The Worker interface of the Web Workers API represents a background task that can be easily created and can send messages back to its creator. Creating a worker is as simple as calling the Worker() constructor and specifying a script to be run in the worker thread.

The WorkerGlobalScope interface of the Web Workers API is an interface representing the scope of any worker. Workers have no browsing context; this scope contains the information usually conveyed by Window objects — in this case event handlers, the console or the associated WorkerNavigator object. Each WorkerGlobalScope has its own event loop.

The WorkerLocation interface defines the absolute location of the script executed by the Worker. Such an object is initialized for each worker and is available via the WorkerGlobalScope.location property obtained by calling self.location.

The WorkerNavigator interface represents a subset of the Navigator interface allowed to be accessed from a Worker. Such an object is initialized for each worker and is available via the WorkerGlobalScope.navigator property obtained by calling window.self.navigator.

The XMLDocument interface represent an XML document. It inherits from the generic Document and does not add any specific methods or properties to it: nevertheless, several algorithms behave differently with the two types of documents.

Use XMLHttpRequest (XHR) objects to interact with servers. You can retrieve data from a URL without having to do a full page refresh. This enables a Web page to update just part of a page without disrupting what the user is doing.

The XMLSerializer interface provides the serializeToString() method to construct an XML string representing a DOM tree.

An XPathExpression is a compiled XPath query returned from document.createExpression(). It has a method evaluate() which can be used to execute the compiled XPath.

The XPathResult interface represents the results generated by evaluating an XPath 1.0 expression within the context of a given node.

An XSLTProcessor applies an XSLT stylesheet transformation to an XML document to produce a new XML document as output. It has methods to load the XSLT stylesheet, to manipulate xsl:param parameter values, and to apply the transformation to documents.