Two complementary families of users' tasks may be identified during database visualization: data browsing and data analysis. On the one hand, data browsing involves extensively exploring a subset of the database using navigational interaction techniques. Classical object database browsers provide means for navigating within a collection of objects and amongst objects by way of their relationships. In temporal object databases, these techniques are not sufficient to adequately support time-related tasks, such as studying a snapshot of a collection of objects at a given instant, or detecting changes within temporal attributes and relationships. Visual data analysis on the other hand, is dedicated to the extraction of valuable knowledge by exploiting the human visual perception capabilities. In temporal databases, examples of data analysis tasks include observing the layout of a history, detecting regularities and trends, and comparing the evolution of the values taken by two or mor...