If you are interested in learning more about the MARC record, check this site out from the Library of Congress.
We use WorldCat to find records for books, to see how many other libraries own a particular book, and many other reasons. You can access WorldCat from the library home page.
Here's the basics for Dewey numbers.
000 Generalities
100 Philosophy & psychology
200 Religion
300 Social sciences
400 Language
500 Natural sciences & mathematics
600 Technology (Applied sciences)
700 The arts
800 Literature & rhetoric
900 Geography & history
If you are interested in learning more about the Dewey Classification System, check this site out from OCLC.
This game is great fun and will help you learn the Dewey Decimal System.
