This is one of the oldest forms of HTTP authentication. In the earliest days of the web this what would be part of seeing a little drop down at the top of a web page where you would need to enter a username and password into your browser.
How does it look?
Basically we have:
Authorization header
With the keyword Basic followed by the username:password but where the username and password are encoded in Base64.
This fragment of Lua code in the translator makes it more clear how this looks:
See the Confluence API for an example of an API which uses this method of authentication.
See https://en.wikipedia.org/wiki/Basic_access_authentication
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