HTTP is an acronym for Hypertext Transfer Protocol, which is the data transfer protocol utilized by the World Wide Web. HTTP defines how data is communicated and the actions that should be taken by browsers and servers. HTTP 1.1 is the current version of HTTP that is commonly used.
HTTP is based on the ability of hypertext to create references connecting multiple documents. As users navigate between documents their HTTP client, or web browser, communicates with web servers according to HTTP.
HTTP was created by Tim Berners-Lee and his colleagues that invented the World Wide Web in 1991. They also developed the technology for web servers and browsers, which interact based on HTTP. HTTP has undergone changes since then, and in 1997 HTTP 1.1 was declared as the official web standard.