The chapter is organized as follows. First, we present the basic concepts and
terminology related to content-based recommenders. A classical framework for pro-
viding content-based recommendations is described, in order to understand the main
components of the architecture, the process for producing recommendations and the
advantages and drawbacks of using this kind of recommendation technique. Section
3.3 provides a thorough review of the state of the art of content-based systems, by
providing details about the classical and advanced techniques for representing items
to be recommended, and the methods for learning user profiles. Section 3.4 presents
trends and future research in the field of content-based recommender systems, while
conclusions are drawn in Section 3.5.