Answered By: Amanda Starkel
Last Updated: Jun 30, 2020     Views: 163

The Butler Libraries use the Library of Congress (LC) Classification System in all three Butler libraries (Irwin, Science, and the Education library on South Campus). The call number on the book's label says where the book is shelved in the library and consists of a letter or two, then a number, followed by decimal-based number that usually stands for the author's name and then the year. For a guide to the LC subjects, visit this LC Classification Outline.

Note: this system is NOT the dewey decimal system, so books are not grouped by genre, they are grouped by subject.

The "Map It" function in Worldcat at provides a helpful visual. The StackMap system generates a link to a floor map coded with the shelf where the item should be located. 

Watch for the signs by the stairs of the Irwin Library, and the signs with the call numbers for the row on the end of each book stack.

If you still are unsure how to find a Butler Libraries book, please visit the Information Commons desk on the first floor of Irwin to ask for help.