How do I find a book...on the shelf?

Library materials are arranged on the shelves in broad subject groups. Within each subject, however, items are distinguished by their unique call number. Each book is assigned a unique call number, a combination of letters and numbers that designate it by subject, and then within that subject. No two books have the same exact call number.

Library of Congress (LC) call numbers, which are used at Pitt, usually consist of two or three lines of letters and numbers. Below is an example of a call number looks like. Each call number is located on either the spine of the book, or on the lower left corner of the front cover.

First, read the LETTERS in the first line: Call numbers are arranged on the shelves alphabetically - call numbers beginning with G first, followed by GN, GV, etc.

Next, read the NUMBERS in the first line: Within the GV's, the arrangement is numerical (GV3 followed by GV7, and then GV 25).

Tip: Unlike Dewey Decimal Classification, numbers in LC go up to 9999. A common mistake would be looking for GV2399 in the GV200s.

The second line is a combination: Within the GV7's, read the letter alphabetically, and then the number as if the number were a decimal. So A5 would read as A.5, which is followed by A55, and then A6. Sometimes a third line indicates when the book was published

Now that you have a basic understanding of shelving rules, if you would like some practice, try the exercise below.