Information like registration numbers and passwords can be saved on the client computer so they do not have to be re-entered. Cookies can be used to store temporary information like items selected from a catalog or the number of times someone has accessed a particular page. Some browsers do not support cookies. Many applications for cookies do not work well when client computers are used by multiple individuals. Cookies have gotten a lot of bad press.
Many people are concerned about potential privacy issues.
To protect privacy browsers must be careful about where they send cookie information. Server software must be capable of interpreting cookies. Typically, cookies are sent to the client from a CGI script executed on the server. Bob's Sushi Cookie Page A JavaScript that asks several questions and saves answers in cookies. A brief specification for persistent state cookies.