Workers (also commonly referred to as Web Workers) are scripts that run in the background independently of any user interface scripts. This allows for long-running scripts that are not interrupted by scripts that respond to clicks or other user interactions, and allows long tasks to be executed without yielding to keep the page responsive.
- An object representing a worker, that is used to communicate with the worker.
- An object representing the identity and state of the user agent (the client).
- FormData is an interface that helps to create a set of key-value pairs representing form fields and their values intended to be sent using XMLHttpRequest.