Cookies can enhance the browsing experience.
For example, if you go to an on-line record store and fill out a form describing your musical tastes, the record store's server may put the information you have entered into a file. The next time you visit that record store site, the server would look to see if a cookie had been set by itself. The server would see the name of the file in the cookie, and retrieve that file from its own hard drive. Then it could shape the record store's web page to reflect the tastes you described on your original visit. Cookies are also used in advertisements on the web, to store information on which ads you have seen and what types of products you may be interested in.