Basic and Bearer show up constantly in an API request's Authorization header โ here's how each is structured and when to use it.
How Basic auth is structured
The string username:password is Base64-encoded and sent as Authorization: Basic <encoded-value>. Base64 is encoding, not encryption โ anyone can decode it instantly โ so this scheme is only safe over HTTPS.
How Bearer token auth is structured
It's sent as Authorization: Bearer <token>, carrying a token issued after login (usually a JWT or OAuth access token) directly. The token itself is the credential โ whoever "bears" it is treated as authenticated.
Which one to use when
Basic is simple enough that it still shows up in server-to-server internal traffic or simple admin APIs, but sending the raw password on every request carries real exposure risk. For ordinary web and mobile APIs requiring user login, a Bearer token โ expirable and revocable โ is the standard.