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Call numbers - how to locate a book on the shelf: Definition

Ten main classes

000 Computer science, information & general works
100 Philosophy & psychology
200 Religion
300 Social sciences
400 Language
500 Science
600 Technology
700 Arts & recreation
800 Literature
900 History & geography


 A call number, with regard to library books, is located on the spine of the book. It is a “unique address” to the location of the book. The library uses the call number system called Dewey Decimal Classification. It was developed by Melvil Dewey. This classification system uses a division of numbers to designate the various classes of subjects. The system uses three digit numbers followed by a decimal point and additional numerals.

Subject Guide