Essay; March 1996; Scientific American Magazine; by Eisenberg; 1 Page(s)

They are known as intelligent agents, those popular new computer programs that sift through the Internet for the things that most interest us. Overwhelmed by all that information on the information highway, we instruct our agents to do a little scouting on our behalf: sort our e-mail, search for the latest articles on knee surgery or shop the World Wide Web for the cheapest compact discs.

There is a small catch, though, to all this convenience. While we or our electronic alter egos are busily looking at Web sites, a good number of the owners and advertisers on these sites are looking right back. All those mouse clicks and keystrokes--which electronic sites we visit, how long we stay and where we go before and after--are not the ephemera they seem. Clickstreams, as they are called, enjoy a digital afterlife in commercial databases, where raw statistics about our on-line behavior are transformed into useful information and then warehoused for future application, sale or barter. These are known as the Clickstreams that keep on giving--to advertisers, mass marketers and lucky venture capitalists.