Web API reference

The Web offers a wide variety of APIs to perform various useful tasks. These can be accessed using JavaScript code, and let you do anything from making minor adjustments to any window or element, to generating intricate graphical and audio effects using APIs such as WebGL and Web Audio.

Each individual interface across all APIs is listed in the index.

There's also a listing of all available events in the event reference.

Document Object Model
The DOM is an API that allows access to and modification of the current document. It allows manipulation of document Node and Element. HTML, XML and SVG have extended it to manipulate their specific elements.
Device APIs
This set of APIs allows access to various hardware features available to Web pages and applications. E.g. Ambient Light Sensor API, Geolocation API, Pointer Lock API, Proximity API, Device Orientation API, Screen Orientation API, Vibration API.
Communication APIs
These APIs let Web pages and applications communicate with other pages or devices. E.g. Network Information API, Web Notifications.
Data management APIs
User data can be stored and managed using this set of APIs. E.g. FileHandle API, IndexedDB.

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