Enter the cookie, technology developed by Netscape Communications Corp. A cookie is a bit of data that a site creator can send back and forth from the site to a person looking at it.
TAILORING AD BANNERS
Companies like Firefly Network (http://www.ffly.com) that develop intelligent agent software can watch users enter a site, see what pages they view and then point to other areas of the site or deliver targeted ad banners.
It's here that consumers get uneasy. Cookies have a bit of a "big brother" aspect, because they are stored on a computer hard drive. Some consumers worry that sites can learn too much about them.
Cookies, for the most part, have very little information. They can't tell anything about the user that the browser isn't already sending to the server, unless it's something the user enters. Cookies aren't able to grab an e-mail address.
Users still concerned about cookies can use Netscape 3.0 or Internet Explorer 3.0, both of which can deliver a warning when a server wishes to send a cookie.