What is a cookie?

Cookies are pieces of information generated by a web server and stored in the user's computer, ready for future access. Cookies are embedded in the HTML information flowing back and forth between the user's computer and the servers. Cookies were implemented to allow user-side customisation of web information. For example, cookies are used to personalize web search engines and to store shopping lists of items a user has selected while browsing through a virtual shopping mall.

For example, when you enter a website that uses cookies, you may be asked to fill out a form which asks for information such as your name and interests. This information is packaged into the cookie and stored for later use. The next time you visit the same website, your browser will send the cookie to the web server and use the information stored to present you with custom web pages that you have set previously.