What is a "stateless protocol" like HTTP?

Question

Lately I have been reading a lot of material about the web and I always see someone mentioning that HTTP is a stateless protocol (stateless Protocol).

Follows a passage taken from RFC 2616 (my emphasis)

The Hypertext Transfer Protocol (HTTP) is an application-level Protocol for Distributed, Collaborative, Hypermedia information systems. It is a Generic, stateless, Protocol which can be used for Many tasks Beyond its use for Hypertext, such as name Servers and Distributed Object management systems, through Extension of its request methods, error codes and headers [47].

What makes HTTP a stateless protocol?

Answer 1

In computing, a stateless protocol (stateless) is a communication protocol that considers each request as an independent transaction that is not related to any previous request, so that the communication consists of independent request and response pairs. A stateless protocol does not require the server to retain information or session status about each communication partner for the duration of multiple requests. In contrast, a protocol that requires maintenance of the internal state on the server is known as a protocol with state.

Examples of stateless protocols include the Internet Protocol (IP), which is the basis for the Internet, and the Hypertext Transfer Protocol (HTTP), which is the basis of data communication for the World Wide Web.

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