If we just put all of our books anywhere in the Library, no one would be able to find anything. Obviously, they need to be organized.
In the late 1800’s, a librarian named Melvil Dewey came up with an organizing system that has become known as the Dewey Decimal System and is used in public and school libraries. If you understand the basics of Dewey, you can find books in most libraries. You probably learned about Dewey in school, but just in case you’ve forgotten, we’re going to give you a little lesson.
If you’re looking for books, you’ll likely look in the card catalog (people still call it that even though it's on a computer and we no longer have cards). (Click here to learn how to use Catalog.) Or you may just browse the shelves to look for books. Whether you use the Catalog or just browse, understanding Dewey is helpful.
CALL NUMBERS.
Every book has a Call Number, which is located on the bottom of the spine of a book and has 2 or more lines. That Call Number is the book’s address – it tells where the book lives.The first line usually has a letter on it, which tells you what section of the Library it lives in. Click here for what the letters in the first line mean.
The second line tells you how to find a specific book. Click here for how to interpret the second line.
First Line of Call Number
| Letter | Section of Library | Location & Comments |
| No letter | Nonfiction | Downstairs |
| F | Fiction | Downstairs |
| B | Biography | Downstairs |
| R | Reference | Downstairs. No book with an "R" can be checked out. |
| RR | Ready Reference | Downstairs. Available only through the Reference Librarian. Includes items like local phone books, government materials, etc. |
| G | Geneology | Upstairs. Also includes local history. No books in this section can be checked out. |
| GR | Genealogy Reference | |
| Young Adult | Downstairs. Librarian term for teens 14 - 18. | |
| YA | Nonfiction | |
| YAF | Fiction | |
| Juvenile | Upstairs. For children under 14. | |
| J | Nonfiction | |
| JF | Fiction | |
| JB | Biography | |
| JR | Reference | |
| E | Easy | Special section for very young children. |
| JC | Cassettes | |
| JCD | Compact Disks | |
| LP | Large Print | Downstairs. For those with difficulty reading regular size print. |
| LR | Locked Room | Upstairs. Very valuable items. Available only through a staff member. |
| V | Videos | Downstairs |
| C | Cassette Tapes | Downstairs |
| CD | Compact Disks | Downstairs |
| VF | Vertical Files | Upstairs and downstairs. File folders with articles and other information on various subjects. Cannot be checked out. |
| MF | Microfilm | Upstairs and downstairs. Cannot be checked out. Ask staff for assistance in using the microfilm readers. |
| TOP |
Second Line of Call Numbers
Fiction is easy because it’s organized by Author, and the second line will be the first three letters of the author’s last name.
Nonfiction is organized by subject and is more complicated, and that’s where Dewey comes in.
A Dewey “Decimal” number always has three digits to the left of the decimal, There are ten major subject categories that correspond to the first digit to the left of the decimal or the Hundreds. The second digit corresponds to the sub categories (Tens) and third digit corresponds to the sub sub categories. After that, you go to digits to the right of the decimal - the more digits, the more specific the classification. There can be any number of numbers to the right of the decimal. However, you really don't need to know the meaning of those digits to the right.
Click on any of the Hundreds below to see the list of corresponding Tens. For a complete list including the sub sub categories, click here.
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
000 Generalities
010 Bibliography
020 Library & information sciences
030 General encyclopedic works
040 Not assigned or no longer used
050 General serials & their indexes
060 General organization & museology
070 News media, journalism, publishing
080 General collections
090 Manuscripts & rare books
100 Philosophy & psychology
110 Metaphysics
120 Epistemology, causation, humankind
130 Paranormal phenomena
140 Specific philosophical schools
150 Psychology
160 Logic
170 Ethics (Moral philosophy)
180 Ancient, medieval, Oriental philosophy
190 Modern Western philosophy 200 Religion
200 Religion
210 Natural theology
220 Bible
230 Christian theology
240 Christian moral & devotional theology
250 Christian orders & local church
260 Christian social theology
270 Christian church history
280 Christian denominations & sects
290 Other & comparative religions
300 Social sciences
310 General statistics
320 Political science
330 Economics
340 Law
350 Public administration
360 Social services; associations
370 Education
380 Commerce, communications, transport
390 Customs, etiquette, folklore
400 Language
410 Linguistics
420 English & Old English
430 Germanic languages German
440 Romance languages French
450 Italian, Romanian, Rhaeto-Romantic
460 Spanish & Portugese languages
470 Italic Latin
480 Hellenic languages Classical Greek
490 Other languages
500 Natural sciences & mathematics
510 Mathematics
520 Astronomy & allied sciences
530 Physics
540 Chemistry & allied sciences
550 Earth sciences
560 Paleontology Paleozoology
570 Life sciences
580 Botanical sciences
590 Zoological sciences
600 Technology (Applied sciences)
610 Medical sciences Medicine
620 Engineering & allied operations
630 Agriculture
640 Home economics & family living
650 Management & auxiliary services
660 Chemical engineering
670 Manufacturing
680 Manufacture for specific uses
690 Buildings
700 The arts
710 Civic & landscape art
720 Architecture
730 Plastic arts Sculpture
740 Drawing & decorative arts
750 Painting & paintings
760 Graphic arts Printmaking & prints
770 Photography & photographs
780 Music
790 Recreational & performing arts
800 Literature & rhetoric
810 American literature in English
820 English & Old English literatures
830 Literatures of Germanic languages
840 Literatures of Romance languages
850 Italian, Romanian, Rhaeto-Romanic
860 Spanish & Portuguese literatures
870 Italic literatures Latin
880 Hellenic literatures Classical Greek
890 Literatures of other languages
900 Geography & history
910 Geography & travel
920 Biography, genealogy, insignia
930 History of ancient world
940 General history of Europe
950 General history of Asia Far East
960 General history of Africa
970 General history of North America
980 General history of South America
990 General history of other areas
