In the last two decades, user profiles have been used in several areas of information technology. In the literature, the vast majority of research works, and systems focus on the creation of profiles (using Data Mining techniques based on user navigation history) and their dynamics are made by means of systematic recreation of the profiles, without using the last used profile. In this talk we propose to formalize the creation, representation, and dynamics of profiles in a Knowledge-Driven perspective. We characterized 4 ways for updating profiles in a belief change perspective.