How does the Dewey Decimal System work?
The first three numbers refer to the broad subject area, and are shelved in numerical order. For example, 945 is shelved before 946.
These numbers are followed by a decimal point. The numbers after the decimal point show the sub-section of the subject area. Again, they are shelved in numerical order. For example, 945.805 is shelved before 945.81.
The numbers will be followed by three letters, these are useful when there are lots of books on the same subject. They might tell you about the book's author, its title or the level of the subject they are about.
You can see the main subject areas below
| 001-099 |
Computer science, information and general work |
| 100-199 |
Philosophy and psychology |
| 200-299 |
Religion |
| 300-399 |
Social sciences |
| 400-499 |
Language |
| 500-599 |
Science |
| 600-699 |
Technology |
| 700-799 |
Art and recreation |
| 800-899 |
Literature |
| 900-999 |
History and geography |
Use the subject index to find out which Dewey Decimal number is used for the subject you want to find books for.