Functional Requirements for Bibliographic Records (FRBR) is a conceptual model for the arrangement of bibliographic records in catalogs and databases which was proposed in IFLA 1997, following a plan for revising Anglo-American Cataloging Rules (AACR). This model is inclined to be separated from the other cataloging rules, and uses a new structure for storing and displaying bibliographic records in order to meet users' information needs, which is the most important purpose of this model. Some unique characteristics of this model can be used for eliminating the problems of current catalogs and designing future ones. In this article, after describing the history of FRBR, and introducing this model as well as the entities which forms it, past studies related to FRBR and the main characteristics of this model are reviewed. In comparison to AACR, the main characteristics of FRBR are: parallel description of primary document, hierarchical structure of bibliographic records, preparing a super record for each document, and determining functions of existing data elements in bibliographic records. The article ends with some criticisms of the model