Have you ever wondered how
library books are assigned their places on the shelves?
Did you know that the call number—the number placed
on the spine of the book—is a code which provides
valuable information about the book?
This page will provide an
introduction to understanding and using library call numbers.
Why Are Call Numbers Necessary?
Each book in the library has
a unique call number. A call number is like an address: it
tells you where the book is located in the library.
Call numbers appear
Note that the same call number
can be written from top-to-bottom, or left-to-right.
Since the mid-70s the Howard
University Libraries have been using the
Library of Congress (LC) Classification
system for call numbers. Before that time, the Dewey
Decimal system was used. Many of the older
books in the Undergraduate Library still have Dewey Decimal
call numbers. To view the Dewey Decimal chart,
and click here
too see how Dewey Decimal call numbers are read.
The LC system uses a combination
of letters and numbers to arrange materials by subjects.
Reading Call Numbers
Putting Call Numbers in Shelf
To understand how call numbers
are put in order in Library of Congress Classification, again
look at each section of the call number.
What Does the Call Number
Remember that Library of
Congress Classification arranges materials by subjects. The
first sections of the call number represent the subject of
the book. The letter-and-decimal section of the call number
often represents the author's last name. And, as you recall,
the last section of a call number is often the date of publication.
Why Is This Important to Know?
Because books are classified
by subject, you can often find several helpful books on the
same shelf, or nearby. For example, within the same call number
LB2395, there are other guides for college study.
Basic Steps in the Research Process
Suggestions for Finding a Topic
Search for Specific Types of Materials
Finding Books by Call Numbers