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How are Books Organized in the Library?

by Megan Babal on 2018-10-01T17:26:14-04:00 | Comments



Did you ever wonder why our library’s books are arranged as they are? Meet the Library of Congress Classification system!

History of Library of Congress Classification 

Our classification system was developed by the United States Library of Congress early in the 20th century as a way to organize its own collection. That library had tried several other shelving orders in the past, but its collection grew so large and covered such a breadth of topics that these original systems were deemed insufficient. No other established classification system out there at the time offered everything the Library of Congress needed, so the librarians there built their own.

In this system materials are arranged on the shelves by subject, enabling books on the same topic to be grouped together. Areas of knowledge are broken down into 21 broad classes, indicated by letters of the alphabet, and the topics within each class are arranged in a loose hierarchy and indicated by combinations of letters and numbers. The system defines a specific classification number to almost every topic held in the Library of Congress collection, the largest library in the world, and new classification numbers can be established as new topics enter the published record.

Classification at Buhl Library

Although created specifically for the Library of Congress, this classification system has also been adopted by many American academic libraries. It allows for a high level of specificity in denoting topics, yet the combination of letters and numbers making up the classification number are relatively short compared to other systems like Dewey Decimal Classification. Also, because the Library of Congress freely shares its cataloging data, its classification numbers for books are readily available to libraries and make for efficient local processing.

Buhl Library made the transition from Dewey Decimal Classification to Library of Congress Classification in 2002. Feeling the library had outgrown Dewey and wanting to align with the research institutions students often went on to attend for graduate work, it was time for change. After almost 2 years of preparations the library closed over summer break 2002 and every one of the 118,718 volumes in the collection was pulled, relabeled, and moved to its new place on the shelves. It was a lot of work, but the library has never looked back!

How to read a Library of Congress Classification call number

The call number for an item in our library is made up of the Library of Congress Classification based on a book’s subject, a notation indicating the book, a year, and occasionally a volume and/or copy number. Call numbers as they display on a spine label show a stack of letters and numbers, breaking the call number down into its separate parts so that you can easily read and interpret it. Here is a quick guide to reading call numbers that will help you understand the order of books on the shelves and enable you to locate the resources you need.


If you ever need help locating a book, a library staff member is always available at the front desk in the library lobby to assist you. We're happy to help you find the resources that you need.


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