1. AbortController & AbortSignal

    Controller object that allows you to abort one or more DOM requests made with the Fetch API.

  2. Accelerometer

    Defines `Accelerometer`, `LinearAccelerationSensor` and `GravitySensor` interfaces for obtaining information about acceleration applied to the X, Y and Z axis of a device that hosts the sensor.

  3. Ambient Light Sensor

    Defines a concrete sensor interface to monitor the ambient light level or illuminance of the device’s environment.

  4. Arrow functions

    Function shorthand using `=>` syntax and lexical `this` binding.

  5. asm.js

    An extraordinarily optimizable, low-level subset of JavaScript, intended to be a compile target from languages like C++.

  6. Async functions

    Async functions make it possible to treat functions returning Promise objects as if they were synchronous.

  7. Audio element

    Method of playing sound on webpages (without requiring a plug-in). Includes support for the following media properties: `currentSrc`, `currentTime`, `paused`, `playbackRate`, `buffered`, `duration`, `played`, `seekable`, `ended`, `autoplay`, `loop`, `controls`, `volume` & `muted`

  8. Web Audio API

    High-level JavaScript API for processing and synthesizing audio

  9. Autofocus attribute

    Allows a form field to be immediately focused on page load.

  10. Auxclick

    The click event for non-primary buttons of input devices

  11. Brotli Accept-Encoding/Content-Encoding

    More effective lossless compression algorithm than gzip and deflate.

  12. CSS all property

    A shorthand property for resetting all CSS properties except for `direction` and `unicode-bidi`.

  13. CSS :any-link selector

    The `:any-link` CSS pseudo-class matches all elements that match `:link` or `:visited`

  14. CSS Filter Effects

    Method of applying filter effects using the `filter` property to elements, matching filters available in SVG. Filter functions include blur, brightness, contrast, drop-shadow, grayscale, hue-rotate, invert, opacity, sepia and saturate.

  15. selector list argument of :not()

    Selectors Level 3 only allowed `:not()` pseudo-class to accept a single simple selector, which the element must not match any of. Thus, `:not(a, .b, [c])` or `:not(a.b[c])` did not work. Selectors Level 4 allows `:not()` to accept a list of selectors. Thus, `:not(a):not(.b):not([c])` can instead be written as `:not(a, .b, [c])` and `:not(a.b[c])` works as intended.

  16. CSS overflow-anchor (Scroll Anchoring)

    Changes in DOM elements above the visible region of a scrolling box can result in the page moving while the user is in the middle of consuming the content. By default, the value of `overflow-anchor` is `auto`, it can mitigate this jarring user experience by keeping track of the position of an anchor node and adjusting the scroll offset accordingly

  17. CSS.supports() API

    The CSS.supports() static methods returns a Boolean value indicating if the browser supports a given CSS feature, or not.

  18. CSS touch-action property

    touch-action is a CSS property that controls filtering of gesture events, providing developers with a declarative mechanism to selectively disable touch scrolling (in one or both axes) or double-tap-zooming.

  19. CSS3 attr() function for all properties

    While `attr()` is supported for effectively all browsers for the `content` property, CSS Values and Units Level 5 adds the ability to use `attr()` on **any** CSS property, and to use it for non-string values (e.g. numbers, colors).

  20. Datalist element

    Method of setting a list of options for a user to select in a text field, while leaving the ability to enter a custom value.

  21. ECMAScript 2015 (ES6)

    Support for the ECMAScript 2015 specification. Features include Promises, Modules, Classes, Template Literals, Arrow Functions, Let and Const, Default Parameters, Generators, Destructuring Assignment, Rest & Spread, Map/Set & WeakMap/WeakSet and many more.

  22. File API

    Method of manipulating file objects in web applications client-side, as well as programmatically selecting them and accessing their data.

  23. CSS Flexible Box Layout Module

    Method of positioning elements in horizontal or vertical stacks. Support includes all properties prefixed with `flex`, as well as `display: flex`, `display: inline-flex`, `align-content`, `align-items`, `align-self`, `justify-content` and `order`.

  24. Form attribute

    Attribute for associating input and submit buttons with a form.

  25. Input Method Editor API

    Provides scripted access to the Input Method Editor (IME). An IME is often used to input characters from East Asian languages by typing roman characters and selecting from the resulting suggestions.

  26. File System Access API

    API for manipulating files in the device's local file system (not in a sandbox).

  27. Object RTC (ORTC) API for WebRTC

    Enables mobile endpoints to talk to servers and web browsers with Real-Time Communications (RTC) capabilities via native and simple JavaScript APIs

  28. Reversed attribute of ordered lists

    This attribute makes an ordered list number its items in descending order (large to small), instead of ascending order (small to large; the default). The order that the list items are displayed in is not affected.

  29. Permissions API

    High-level JavaScript API for checking and requesting permissions

  30. Ping attribute

    When used on an anchor, this attribute signifies that the browser should send a ping request the resource the attribute points to.

  31. Push API

    API to allow messages to be pushed from a server to a browser, even when the site isn't focused or even open in the browser.

  32. SDCH Accept-Encoding/Content-Encoding

    Shared Dictionary Compression over HTTP

  33. Speech Recognition API

    Method to provide speech input in a web browser.

  34. Speech Synthesis API

    A web API for controlling a text-to-speech output.

  35. Srcset and sizes attributes

    The `srcset` and `sizes` attributes on `img` (or `source`) elements allow authors to define various image resources and "hints" that assist a user agent to determine the most appropriate image source to display (e.g. high-resolution displays, small monitors, etc).

  36. User Timing API

    Method to help web developers measure the performance of their applications by giving them access to high precision timestamps.

  37. WebAssembly

    WebAssembly or "wasm" is a new portable, size- and load-time-efficient format suitable for compilation to the web.

  38. WebCodecs API

    API to provide more control over the encoding and decoding of audio, video, and images.

  39. WebHID API

    Enables raw access to HID (Human Interface Device) commands for all connected HIDs. Previously, an HID could only be accessed if the browser had implemented a custom API for the specific device.

  40. WebVR API

    API for accessing virtual reality (VR) devices, including sensors and head-mounted displays. Replaced by the [WebXR Device API](/webxr).

  41. WebXR Device API

    API for accessing virtual reality (VR) and augmented reality (AR) devices, including sensors and head-mounted displays.

  42. cssstylesheet api: `cssstylesheet()` constructor

  43. hid api

  44. lock api

  45. usb api

  46. html element: a

  47. axios.js

  48. google chrome for android

  49. uc browser for android

  50. qq browser for android