University of Maryland Eastern
Shore
Frederick Douglass Library
Using Call
Numbers to Find a Book
Understanding Call Numbers
Each book, magazine/journal, and most other materials in the library have a call number. That number is the book’s home address—the place it physically occupies on the shelf. Just as your house number is unlike your neighbor’s, no two items have the same number.
Most college or university libraries use the Library of Congress System to catalog and locate books. It is a flexible system, using letters, numbers, and decimal points to identify an item’s content and location on the shelf. To understand the system, look at the three call numbers below
(1) Q1.S3, (2) QE531.2.B64, (3) QA76.76.H94.M88
In the first example above, a book with a call number beginning with the letter (Q) will be found after all the books on the A-P shelves.
A book with the call number (QE) comes after all the (QA-QD’s).
The book (QA76.76.H94.M88) would be after all books with call numbers QA76.76.(A-G).
The final letter, representing the author’s last name, is also read alphabetically so that .M88 would fall after (A-L) and before (N-Z).
The number(s) following immediately after the first letter(s) (QA), for example, are arranged in simple numerical order. That is, (QA 1, QA 10, QA 40, QA 100) etc.
The numbers after the decimal point are in decimal form; for example (QA76.76, .761, .762, 763 would all become before QA76.8.
Finding a Book
Now that you understand the elements that make up a call number, it is time to actually find a book, but before you head for the stacks check two or three more things.
Which collection the book is shelved in—the Stacks, the Black Collection, Special Collections Black, Media, or Reference
It’s availability—whether it is checked out.
The final step is to go to the collection where the book is shelved and look at the shelf labels at the end of each shelf. Once you have found the right range, apply the above rules to find the book or periodical you need.
Lois Peterson 1/03