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How to Read Call Numbers

Where are the Deweys?

Deweys in the Owen Science and Engineering Library are on the 3rd floor.  Look for the signs as you get out of the elevator.

Dewey call numbers in the Holland & Terrell libraries are located on the Basement floor in Compact shelving. (see map below)

Holland and Terrell Basement Floor

Map of Terrell Basement floor with arrow directing to labeled Deweys section.


How to Read Dewey Decimal Call Numbers

Like Library of Congress call numbers, Dewey Decimal call numbers group books together by broad topic or classification (number before the decimal), and then use further letters and numbers to group books into more specific topics and subtopics (letters and numbers after the decimal).

While the call numbers appear horizontally in Search It (the WSU Libraries online catalog), they will appear vertically on the spine or edge of the book.

For example, to read the Dewey Decimal call number in Search It:  630.51 P884

630.51: The number in front of the decimal is read as a whole number (six hundred and thirty), then treat the rest as a decimal. 630.51 would come between 630.5 and 630.52.

P884: For the final number, go to the letter first and then read the rest as the whole number. P884 would come between P883 and P885.

The call number appears horizontally on the spine:

visual aid for how call numbers are ordered on a shelf of books

(Example taken from the U. of Chicago libraries.)


Dewey call numbers on the Shelf

Close up of Dewey call numbers on books on a shelf.

Dewey Decimal Classification

Call numbers group materials on similar subjects together to facilitate browsing. So, if you find one book that closely matches your topic, you will likely find others next to it on the shelf that fit with your research. The beginning letters of a Dewey Decimal call number indicate what broad classification your book is in.

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

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