Understanding Call Numbers

What are call numbers for?

Each book in the library has a unique call number. A call number is like an address: it tells us where the book is located in the library.  Call numbers appear 


Note that the same call number can be written from
top-to-bottom, or left-to-right. 

The SE Library uses the Dewey Decimal Classification for call numbers. This system uses a combination of letters and numbers to arrange materials by subjects.

Reading Call Numbers

Read call numbers line by line

Putting Call Numbers in Shelf Order

To understand how call numbers are put in order in the Dewey Decimal Classification, again look at each section of the call number.

Different call numbers in order

What does the call number mean?

Remember that the Dewey Decimal Classification arranges materials by subjects. The first sections of the call number represent the subject of the book. The cutter number section of the call number often represents the author's last name. And, as you probably recall, the last section of a call number is often the date of publication.  For example:

Lines of call number and explanation

Why is this important to know?
Because books are classified by subject, you can often find several helpful books on the same shelf, or nearby. For example, within the same call number 973.736, there are other books on the early 1864 period of the Civil War.

Similar books shelved together

Since the Dewey Decimal Classification arranges materials by subjects, knowing the numbers for your subject area gives you a place to start browsing the shelves.

Lines of call number and explanation

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