Cookies are short pieces of data used by web servers/sites to help identify web users. Cookies are not programs that can run amok. They are merely bits of text, a tool created by Netscape in 1994 to enable Web sites to identify repeat visitors. Sent primarily by the biggest commercial Web sites, cookies get stored on your computer. If you return to the site, your browser will send back the cookie, a gesture roughly equivalent to saying, "Hey, it's me again."