Library classification of a piece of work consists of two steps. Firstly. the" abruptness" of the material is ascertained. Next, a call number(essentially a book's address), based on the basification system in use at the particular library will be assigned to the work using the notation of the system. It is important to note that unlike subject heading or thesauri where multiple terms can be assigned to the same work, in library classification systems, each work can only be placed in one class. This is due to shelving purposes: A book can have only one physical place. However in classified catalogues one may have main entries as well as added entries. Most classifications stems Like the Dewey Decimal Classification (DDC) and Library of Congress classification also add a code number to each work which adds a code for the author of the work. Classification systems in Iibraries generally play two roles. Firstly they facilitate subject access by allowing the user to find out what works or documents the library has n on a certain subject. Secondly, they provide a known location for the information source to be located (e.g where it is shelved).The primary aim of writing this book on this subject is to present the subject matter in a concise and an intelligible form, keeping in view the needs of the average student.