Hypertext Transfer Protocol (HTTP) is the protocol for communication between a web client (usually a web browser) and a web server. This protocol is not only used a lot on the World Wide Web, but also on local networks (we then speak of an intranet).

HTTP defines which questions (the English term for this is requests) a client can ask a server and which answers (the English term is responses) a web server can return. Each question contains a URL that refers to a web component or a static object such as a web page or image.

Hypertext Transfer Protocol Secure (HTTPS) is an extension of the Hypertext Transfer Protocol (HTTP). It uses encryption for secure communication over a computer network, and is widely used on the Internet. In HTTPS, the communication protocol is encrypted using Transport Layer Security (TLS) or, formerly, Secure Sockets Layer (SSL). The protocol is therefore also referred to as HTTP over TLS, or HTTP over SSL.