We compare the usage of a Digital Library with many different categories of collections, by examining its log files for a period of twenty months, and we conclude that the access points that the users mostly refer to, depend heavily on the type of content of the collection, the detail of the existing metadata and the target user group. We also found that most users tend to use simple query structures (e.g. only one search term) and very few and primitive operations to accomplish their request. Furthermore, as they get more experienced, they reduce the number of operations in their sessions.