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Understanding Call Numbers

Find books on the shelves more quickly with this quick overview of how to read Library of Congress call numbers.

Reading Call Numbers

How do you read call numbers?

Read call numbers by each separate part. See the image below to learn about the different parts.


What is the purpose of call numbers?

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 on the spines of books and in the online catalog.

Image illustrating where call numbers are found on physical items and where they are located in the library catalog.

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

Milner Library uses Library of Congress Classification for call numbers. This system uses a combination of letters and numbers to arrange materials by subjects.

In the Catalog, you can find the location of an item and its availability. For maps showing the path to the different locations, look at the Find an Item in the Library tab.

Image of a catalog record of a book located on the 6th floor, with the call number LB2395 .D739 2010