The DataStoreCursor interface of the Data Store API represents a cursor that allows apps to iterate through a list of DataStoreTask objects representing the change history of the data store, for use when synchronizing the data.
The DataStoreTask interface of the Data Store API represents a record changed in the data store when a DataStoreCursor is used to iterate through the data store's change history.
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 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that any functional events (like FetchEvent) are not dispatched until it upgrades database schemas and deletes the outdated cache entries.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 HMDVRDevice interface of the WebVR API represents a head mounted display, providing access to information about each eye, and allowing us to modify the current field of view.
The IDBEnvironment interface of the IndexedDB API contains the indexedDB property, which provides access to IndexedDB functionality. It is the top level IndexedDB interface implemented by the window and Worker objects.
A MediaQueryList object maintains a list of media queries on a document, and handles sending notifications to listeners when the media queries on the document change.
The MediaRecorder interface of the MediaRecorder API provides functionality to easily record media. It is created by the invocation of the MediaRecorder() constructor.
The MediaTrackConstraints dictionary is used to describe a set of capabilities and the value or values each can take on. A constraints dictionary is passed into applyConstraints() to allow a script to establish a set of ideal values and/or preferred ranges of values for the track, and the most recently-requested set of custom constraints can be retrieved by calling getConstraints().
The MediaTrackSupportedConstraints dictionary establishes the list of constrainable properties recognized by the user agent or browser in its implementation of the MediaStreamTrack object. An object conforming to MediaTrackSupportedConstraints is returned by MediaDevices.getSupportedConstraints().
The NavigatorConcurrentHardwaremixin adds to the Navigator interface features which allow Web content to determine how many logical processors the user has available, in order to let content and Web apps optimize their operations to best take advantage of the user's CPU.