HTTP protocol is the abbreviation of Hyper Text Transfer Protocol, which is a transfer protocol used to transfer hypertext from the World Wide Web (WWW: World Wide Web) server to the local browser. .
HTTP is a communication protocol based on TCP/IP to transfer data (HTML files, image files, query results, etc.).
HTTP message structure syntax
HTTP is based on the client/server (C/S) architecture model. It exchanges information through a reliable link and is a stateless request/response protocol.
An HTTP "client" is an application (a web browser or any other client) that connects to a server for the purpose of sending one or more HTTP requests to the server.
An HTTP "server" is also an application (usually a Web service, such as an Apache Web server or an IIS server, etc.) that receives client requests and sends HTTP response data to the client.
HTTP uses Uniform Resource Identifiers (URI) to transmit data and establish connections.
HTTP message structure example
GET /hello.txt HTTP/1.1 User-Agent: curl/7.16.3 libcurl/7.16.3 OpenSSL/0.9.7l zlib/1.2.3 Host: Accept-Language: en, mi