A comparative expertise level-based discovery system infers an expertise level associated with a system user from a plurality of usage behaviors and compares this expertise level with expertise levels associated with computer-implemented objects. One or more of the computer-implemented objects are selected for delivery to the user in accordance with a comparison of the inferred expertise level of the user and the expertise levels associated with the computer-implemented objects. The expertise levels associated with the computer-implemented objects may be inferred from information within the objects such as text and/or may be inferred from usage behaviors. Inferences of interests of the user may further inform the selection of one or more of the computer-implemented objects for delivery to the user. Explanations for the delivery of the computer-implemented objects may be provided to the user.