STARquest I: Library Services & Resources
3d. Then what?
Each of the classifications is broken down further with the addition of a second letter. For example, although Q is used for books about science in general,
- QA is for mathematics
- QB is for astronomy
- QC is for physics
- QD is for chemistry
Other letters of the alphabet are assigned to other areas of knowledge.
A complete guide to the Library of Congress Classifications is available from the library's Web page. Under Research assistance, click on Tutorials, guides and how-to's. Then from the How-to section, select Use the LC Classification System.