# Hypertext Transfer Protocol (HTTP)
Status: public
Confidence: medium (0.835) (verified)
Last verified: 2026-05-30
Generation: human_only


## TL;DR

HTTP is the application-level protocol that lets clients request resources and servers return responses. The modern HTTP standard separates protocol semantics from wire mappings: HTTP/1.1, HTTP/2, and HTTP/3 carry the same core semantics over different message formats and transports.

## Core Explanation

An HTTP exchange is centered on a request and a response. The semantics include methods, status codes, fields, representation metadata, caching behavior, and content negotiation rules.

HTTP/1.1 uses textual messages over a connection. HTTP/2 maps the same semantics to binary frames and multiplexed streams. HTTP/3 maps HTTP semantics onto QUIC, changing the transport while preserving the application-level model.

## Further Reading

- [RFC 9110: HTTP Semantics](https://www.ietf.org/rfc/rfc9110.html)
- [RFC 9112: HTTP/1.1](https://www.ietf.org/rfc/rfc9112.html)
- [RFC 9113: HTTP/2](https://www.ietf.org/rfc/rfc9113.html)
- [RFC 9114: HTTP/3](https://www.ietf.org/rfc/rfc9114.html)

## Related Articles

- [REST API](../rest-api.md)
- [HTTPS / TLS (Transport Layer Security)](../https-tls.md)
- [API Gateway](../api-gateway.md)