Hypertext Transfer Protocol

The Hypertext Transfer Protocol (HTTP) is an application layer protocol in the Internet protocol suite model for distributed, collaborative, hypermedia information systems.[1] HTTP is the foundation of data communication for the World Wide Web, where hypertext documents include hyperlinks to other resources that the user can easily access, for example by a mouse click or by tapping the screen in a web browser.

Hypertext Transfer Protocol
International standardRFC 1945 HTTP/1.0 (1996)

RFC 2068 HTTP/1.1 (1997)
RFC 2616 HTTP/1.1 (1999)
RFC 7230 HTTP/1.1: Message Syntax and Routing (2014)
RFC 7231 HTTP/1.1: Semantics and Content (2014)
RFC 7232 HTTP/1.1: Conditional Requests (2014)
RFC 7233 HTTP/1.1: Range Requests (2014)
RFC 7234 HTTP/1.1: Caching (2014)
RFC 7235 HTTP/1.1: Authentication (2014)
RFC 7540 HTTP/2 (2015)

RFC 7541 HTTP/2: HPACK Header Compression (2015)
Developed byinitially CERN; IETF, W3C
Introduced1991; 30 years ago (1991)

Development of HTTP was initiated by Tim Berners-Lee at CERN in 1989. Development of early HTTP Requests for Comments (RFCs) was a coordinated effort by the Internet Engineering Task Force (IETF) and the World Wide Web Consortium (W3C), with work later moving to the IETF.

HTTP/1 was first documented (as version 1.1) in 1997.[2]

HTTP/2 is a more efficient expression of HTTP's semantics "on the wire", and was published in 2015, and is used by 45% of websites; it is now supported by virtually all web browsers[3] and major web servers over Transport Layer Security (TLS) using an Application-Layer Protocol Negotiation (ALPN) extension[4] where TLS 1.2 or newer is required.[5][6]

HTTP/3 is the proposed successor to HTTP/2,[7][8] and two-thirds of web browser users (both on desktop and mobile) can already use HTTP/3, on the 20% of websites that already support it; it uses QUIC instead of TCP for the underlying transport protocol. Like HTTP/2, it does not obsolete previous major versions of the protocol. Support for HTTP/3 was added to Cloudflare and Google Chrome first,[9][10] and is also enabled in Firefox.[11]