Marketing on the World Wide Web (the Web) is a significant business. Users often purchase products through a company's Website. Further, advertising revenue can be generated in the form of payments to the host or owner of a Website when users click on advertisements that appear on the Website. The amount of revenue earned through Website advertising and product sales may depend on the Website's ability to provide marketing material or other Web content that is targeted to a specific user ID, based on the interests associated with the user ID. A user ID is a unique identifier used to identify a particular system used to access a Website, for example, an IP address, a user name, and the like. Providing targeted Web content may depend on the ability to generate a useful user profile.