cookie

A message given to a Web browser by a Web server. The browser stores the message in a text file. The message is then sent back to the servereach time the browser requests a page from the server.

The main purpose of cookies is to identify users and possibly prepare customized Web pages for them. When you enter a Web site using cookies, you may be asked to fill out a form providing such information as your name and interests. This information is packaged into a cookie and sent to your Web browser which stores it for later use. The next time you go to the same Web site, your browser will send the cookie to the Web server. The server can use this information to present you with custom Web pages. So, for example, instead of seeing just a generic welcome page you might see a welcome page with your name on it.

The name cookie derives from UNIX objects called magic cookies. These are tokens that are attached to a user or program and change depending on the areas entered by the user or program.

session cookie

Also called a transient cookie, a cookie that is erased when the user closes the Web browser. The session cookie is stored in temporary memory and is not retained after the browser is closed. Session cookies do not collect information from the user’s computer. They typically will store information in the form of a session identification that does not personally identify the user.

persistent cookie

Also called a permanent cookie, or a stored cookie, a cookie that is stored on a user’s hard drive until it expires (persistent cookies are set with expiration dates) or until the user deletes the cookie. Persistent cookies are used to collect identifying information about the user, such as Web surfing behavior or user preferences for a specific Web site.