HTTP cookie

HTTP cookies, sometimes known as web cookies or just cookies, are parcels of text sent by a server to a web browser and then sent back unchanged by the browser each time it accesses that server.  HTTP cookies are used for authenticating, tracking, and maintaining specific information about users, such as site preferences and the contents of their electronic shopping carts. The term "cookie" is derived from "magic cookie," a well-known concept in unix computing which inspired both the idea and the name of HTTP cookies.
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<World-Wide Web> A packet of information sent by an HTTP server to a World-Wide Web browser and then sent back by the browser each time it accesses that server. Cookies can contain any arbitrary information the server chooses and are used to maintain state between otherwise stateless HTTP transactions. Typically this is used to authenticate or identify a registered user of a web site without requiring them to sign in again every time they access that site. Other uses are, e.g. maintaining a "shopping basket" of goods you have selected to purchase during a session at a site, site personalisation (presenting different pages to different users), tracking a particular user's access to a site.
http://www.illuminatus.com/cookie.
(1997-01-15)