The letter at the beginning of the call number associates the item with a broad subject area. The rest of the letters and numbers in each call number refine the subject area. This way, all the items about a certain topic can be shelved close to one another in the library's stacks (book shelves).
(Charts with this information are posted throughout the library.)
| Letter | Subject | Location |
| A | General Works | Floor 6 |
| B | Philosophy, Psychology, Religion | Floor 6 |
| C | Archaeology, Genealogy, Biography | Floor 6 |
| D | History: General, Old World | Floor 6 |
| E | History: New World | Floor 6 |
| F | History: New World | Floor 6 |
| G | Geography, Anthropology, Recreation | Floor 6 |
| H | Social Science | Floor 5 |
| J | Political Science | Floor 5 |
| K | Law | Floor 3 |
| L | Education | Floor 5 |
| M | Music | Floor 5 |
| N | Fine Arts | Floor 5 |
| P | Language & Literature | Floor 4 |
| Q | Science, Mathematics | Floor 1 |
| R | Medicine, Health | Floor 1 |
| S | Agriculture, Aquaculture, Wildlife | Floor 1 |
| T | Technology, Engineering | Floor 1 |
| U | Military & Naval Sciences | Floor 6 |
| V | Military & Naval Sciences | Floor 6 |
| Z | Bibliography & Library Science | Floor 6 |