Cookies are small text files that are saved on your computer by your browser. They help sites keep track of you. Without cookies, a site would be unable to remember your preferences or keep track of selections that you have made on different pages.
Cookies usually contain a name, a value, expiration date, and the site that it came from.
The most common type of cookie is called a visitor cookie. Basically what this cookie does is keep track of how many times you return to a site. Each time you visit a site, it opens the cookie saved on your computer and increases its value one higher. This is benficial to the webmaster and end user. It lets the webmaster know which pages are recieving multiple visits from the same users.