i got this from howstuffworks.com, that's a great resource. they
say that it's a piece of text that's stored in your hard drive by
the Web Browser (IE, Safari, FireFox, etc.). For example, a Web
site might generate a unique ID number for each visitor and store
the ID number on each user's machine using a cookie file [Got this
piece of text from: http://computer.howstuffworks.com/cookie1.htm]
http://www.answers.com/topic/cookie-technology?cat=technology
Really, look it up.