When looking for resources in a library, it is a good idea to understand how everything is organized. Many libraries use the Dewey Decimal System to organize materials.
The Dewey Decimal System uses a numerical hierarchy where each work is identified by at least four numbers, with a decimal after the third number. The more numbers after the decimal, the more specific the subject is. For example, 746.92 is the call sign for fashion design.
The first number of the Dewey call sign (called the first summary) indicates the class or topic:
- 0: General information
- 1: Philosophy and psychology
- 2: Religion
- 3: Social sciences
- 4: Language
- 5: Science and mathematics
- 6: Technology and applied sciences
- 7: Arts and recreation
- 8: Literature
- 9: History, geography, and biography
The next two numbers (called the second summary or the hundred divisions) indicate the area of study. Some examples:
- 020: Library and information services (the first number, 0, indicates this belongs to the General Information class)
- 710: Landscaping (the first number, 7, indicates this belongs to the Arts and Recreation class)
- 410: Linguistics (the first number, 4, indicates this belongs to the Language class)
After the class number, there is a decimal followed by another number (or set of numbers) that further classifies the subject.
