HTTP is a stateless protocol. This means the server is not required to maintain state for a user in between
a user's HTTP requests. One common solution is to use HTTP cookies, which are text strings stored by a user's web
browser. Typically, a session identifier provided by an HTTP server is stored in a cookie. This cookie is
then sent with every request to the server, and the server is able to match the session id with stored
state for the user. Session identifiers normally expire within a few minutes, hours or days, depending on
the server settings.
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