HTTP (“HyperText Transfer Protocol”) is the protocol the web runs on.
At a high level it’s request/response:
- client sends a method (
GET,POST, etc.) - server sends back a status code, headers, and optionally a body
Classic HTTP traffic is unencrypted plaintext over TCP, usually on port 80. HTTPS is the secure version used in practice for real sites.
It is also stateless by default, so sessions/auth are usually handled with cookies or tokens layered on top.