Without the knowledge of the Bush administration, an outside contractor has been using Internet tracking technologies that may be prohibited to analyze usage and traffic patterns on the White House's Web site, an official said Thursday.

The disclosure – the second such revelation in a matter of days – came in response to questions posed by The Associated Press.

The White House Web site uses what's known as a Web bug to anonymously keep track of who's visiting and when. A Web bug is essentially a tiny graphic image - a dot, really - that's virtually invisible. In this case, the bug is pulled from a server maintained by WebTrends and lets the traffic analytic company know that another person has visited a specific page on the site.
http://www.cbsnews.com/stories/2005/12/30/politics/main1172239.shtml?cmp=EM8705