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.
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".
This Fetch API interface 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 Referrer-Policy HTTP header controls how much referrer information (sent with the Referer header) should be included with requests. Aside from the HTTP header, you can set this policy in HTML.
The credentials read-only property of the Request interface indicates
whether the user agent should send or receive cookies from the other domain
in the case of cross-origin requests.
The mode read-only property of the Request interface contains the mode of
the request (e.g., cors, no-cors, same-origin, navigate or websocket.) This
is used to determine if cross-origin requests lead to valid responses, and
which properties of the response are readable.
