Basic Authentication

Basic authentication is a simple authentication scheme built into the HTTP protocol. The client sends HTTP requests with the Authorization header that contains the word Basic word followed by a space and a base64-encoded string username:password. For example, to authorize as demo / p@55w0rd the client would send^[1]:

Authorization: Basic ZGVtbzpwQDU1dzByZA==

It is specified in RFC 7617 from 2015, which obsoletes RFC 2617 from 1999.

Note: Because base64 is easily decoded, Basic authentication should only be used together with other security mechanisms such as HTTPS/SSL.

Source:
[1] wagger.io/docs/specification/authentication/basic-authentication/