Dewey Decimal Classification (DDC)

How does it work?

The DDC system divides all knowledge into 10 main categories, each of which is divided into sub-categories. The system groups related items together according to discipline/subject, making it easier for the user to retrieve information. The 10 main broad categories are:

000 Generalities
100 Philosophy & psychology
200 Religion
300 Social sciences
400 Language
500 Natural sciences & mathematics
600 Technology (Applied sciences)
700 The arts - Fine and decorative arts
800 Literature & rhetoric
900 Geography & history

The DDC System moves from the general (broad) to the specific (narrow). Each of the above categories is divided into narrower sub - categories, for example:

600 Technology

610 Medical sciences, Medicine
620 Engineering & allied operations
630 Agriculture & related technologies
640 Home economics & family living
650 Management & auxiliary services
660 Chemical engineering
670 Manufacturing
680 Manufacture for specific uses
690 Buildings

Each of these categories is in turn divided into more specific sub-categories, e.g. 611, 612, 613, etc.