Abstract: A computer apparatus and a method is described for establishing a global interest profile of a user. At least one local server and an enterprise server communicate with the user via a communication channel. The local server assigns a local ID to the user. The enterprise server assigns to the user a global ID and links the local ID and local user information with the global ID to form a global interest profile of the user. The identity of the users is not shared between servers, thereby maintaining the privacy of the user.

Abstract: A system for providing advertisements from a central server to viewers who access web sites. The central server stores both advertisements which are to be displayed and an information data base. The data base includes information about viewers, information about the characteristics of particular web sites and other information relevant to which advertisements should be displayed for particular viewers. Proposed bids submitted by different advertisers are evaluated in real time in order to determine which particular advertisement will be displayed to a viewer. Each proposed bid can specify a price or amount that the advertiser is willing to pay for the opportunity to display an advertisement (a) to a viewer who has a particular set of characteristics and (b) on a web site and web page that meets a particular set of criteria.