Informations that are given by a Web server to your browser the first time you go to a site hosted by that server. Then it is updated at each visit. Your browser records these data on your hard disk and the server also keeps informations about you such as user name and password if there is one for that site, pages of the site you have opened and if applicable orders you have made on the site.

           They can be useful for things like page personalization and avoiding you to retype your username and so on. But many users consider cookies an invasion of privacy. There are different types of cookies. Some are automatically erased when the user closes his browser. Others remain stored on your hard disk but normally they always got an expiration time after which they are automatically erased. You can somehow control cookies with your browser's preferences. Each browser has its own way of changing parameters. If you're using Internet Explorer, on some versions go to the Tools menu and select Internet Options. Within the Internet Options window, select the Advanced tab at the top right, scroll down until you see a selection titled "Cookies" and there may be a box "Always accept cookies" which you can check or not. Or you can play on the security level for Internet. But if you set too high a security level or do not accept cookies at all some programs are liable to complain or not to work properly anymore. The default settings are normally correct.

           The origin of this term is somewhat obscure.

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