Purposes of a Library Catalogue 

Libraries generally acquire reading and reference materials in various physical forms, which will be utilised by users for study, reference, research and other purposes. These materials are constantly under consultation or in circulation and therefore, at any given point of time, some of these materials may not be available on the shelves in the library. 

These reading and reference materials may also be in different physical forms such as printed documents, microfilms or machine-readable forms. They are located and shelved at different place such as sections, rooms, floors in the library, depending upon the most appropriate form of storage. 

Because of these reasons, it is necessary that a library prepares and provides a public record of all the materials irrespective of their physical forms-acquired by it in order to give the readers an idea of the entire collection possessed by it. 

So the main objective of a library catalogue is to aid readers in making use of the collection of the library by providing author, subject, title and other approaches to the collection. The primary purpose of a library catalogue is to serve as a guide to the collection of materials. Basically, it reveals to the users the document or non- document materials contained in the library and aids them in finding out whether the materials of their interest are available in the library or not. In other words, a library catalogue serves as a key to the library collection as well as location or as a retrieval tool.