A system for customizing content and presentation of content for computer users is disclosed. The system monitors and records a user's navigational choices to determine the user's needs and preferences for subsequent computer displays. Displays are customized in accordance with the user's needs and preferences. In a preferred embodiment of the present invention, an electronic marketing and shopping system accessible via the WWW is described. The shopping environment--including the opportunities presented to the shopper (content) and the appearance of the displays (presentation of content)--is customized according to the shopper's preferences. The functions of data collection and display customization are performed automatically by the electronic shopping system. To customize the environment, various attributes of Web pages or other displays provided by participating merchants are modified as they are accessed by shoppers using the system.