Cookies and Internet Privacy Student José Amador likes to use his email account on yahoo.com. “I find paper to be obsolete,” he says. Amador is not concerned about the privacy of this account. Perhaps, though, he and many other people who use Yahoo email should be worried. The actions of all Yahoo Mail users are tracked. Yahoo tracks user actions, in part, using "cookies." Cookies are small files that record visits to web pages. When you open a cookie-serving web page, the web server sends one or more of these files to your browser. Cookies will usually contain a number unique to that browser. Then, the next time the browser opens that particular page, the website will send a new cookie and retrieve the old one. This allows sites to compile lists of how often visitors visit a particular page and when they visit it. By themselves, cookies cannot reveal your identity. All these files can do is store information about domain names and the visitor's approximate location. That said, if the site requires registration and login, such as is the case with Yahoo email, site administrators can easily combine the two data streams. Furthermore, cookies cannot transmit viruses. They are just text files and therefore prevent this danger. Readers who want to view the cookies stored in their browser should look for a file called cookies.txt on PCs or a file called MagicCookie on Macs. The first browser that could handle cookies was Netscape Navigator 1.0. Cookies have become common on the web since the browser first came out in 1995. According to one report, 26 of the top 100 websites use these files. Sites that use cookies include AltaVista, all pages of the GeoCities domain, and the web version of the New York Times. The New York Times is very similar to Yahoo Mail in that it requires you to accept cookies. Most sites, however, do not require browsers to accept cookies. Website administrators say that the main purpose of cookies is not to track Internet browsing habits. Rather, they argue that cookies allow users to personalize their web experience. Services like My Yahoo wouldn't work as well without cookies.