A small piece of information that is automatically stored on a client computer by a Web browser and referenced to identify repeat visitors to a Web site and to tailor information in anticipation of the visitor's interests. Note: Some privacy advocates have objected to the use of cookies without a user's consent. 2. A general mechanism that server side connections (such as CGI scripts) can use both to store and to retrieve information on the client side of the connection. Note 1: A server, when returning an HTTP object to a client, may also send a piece of state information that the client will store. Included in that state object is a description of the range of URLs for which that state is valid. Any future HTTP requests made by the client that fall in that range will include a transmittal of the current value of the state object from the client back to the server. The state object is called a cookie. This simple mechanism provides a tool that enables new types of applications to be written for Web-based environments. Shopping applications can now store information about the currently selected items, for-fee services can send back registration information and free the client from retyping a user ID on subsequent connections, sites can store per-user preferences on the client, and have the client supply those preferences every time that site is accessed. Note 2: Session cookies are volatile in that they disappear at the end of a session, whereas persistent cookies are retained from one session to the next. Synonym magic cookie.