Dewey Decimal Classification System

Most books in the Learning Resources Center are arranged by the Dewey Decimal classification system. The system, designed by Melvil Dewey in 1873, is used throughout the world in various types of libraries and in several languages. 

The Dewey system consists of three basic groupings organized by disciplines or fields of study. In the first group, or summary there are ten main classes. In the second summary there are 100 divisions. The third summary consists of 1,000 sections. The Dewey decimal number you see on a book has been generated using the three summaries. Each digit in the number refers to a part of the three summaries. The first digit refers to one of the ten main classes, the second digit refers to one of the 100 divisions, and the third digit refers to one of the 1,000 sections.

The Dewey number used to identify a book describes what the book is about. For example, if a book has the number 975, we know it is about the history of the southeastern United States. We know this because all books in 900's deal with Geography and History. Books in the 970's deal with the general history of North America, and books in the 975's deal with the southeastern United States.

900 - Geography and History
970 - General History of North America
    →975 - Southeastern United States


Dewey's Ten Main Classes

000 Generalities

100 Philosophy and Psychology

200 Religion

300 Social Sciences

400 Language

500 Natural Sciences and Mathematics

600 Technology (Applied Sciences)

700 The Arts (Fine and Decorative Arts)

800 Literature and Rhetoric

900 Geography and History


Links to more information on Dewey

Brief summary of the Dewey system

Dewey Decimal Classification Homepage