Functional requirements for bibliographic records (FRBR) is a complex conceptual model that is not easy for everyone to understand. In this paper FRBR’s status as a model is examined in detail – to explicate more fully what it is, what it is not and what it attempts to do. The focus of the discussion throughout this paper is the Group 1 entities: work, expression, manifestation and item. Several strategies are presented to clarify the more difficult abstract entities in FRBR, which are work and expression. Because FRBR is the most recent of a series of conceptual models used in library cataloging, models used prior to FRBR are described and compared to FRBR.