Call Numbers

What are Call Numbers

Most items in the collection are arranged by subject. Each item is assigned a unique call number that indicates not only where the item is located but provides other valuable information about the item as well. Items about the same subject have similar call numbers. Therefore, they are grouped together on the shelf. This makes it easier for users to browse items on a particular topic.

Location Prefix

Some call numbers are preceded by a location prefix. A location prefix means that the item belongs to a specific collection, is shelved in a special place, and may have circulation restrictions. For example, in the call number, Ref AG243 .G87 1992 , the Ref prefix indicates that the item is shelved in the Reference Collection. Items in the Reference Collection do not circulate.

Library of Congress (LC) Call Numbers

LC call numbers always begin with a letter of the alphabet that identifies the main class or subject of the item. LC main classes and their corresponding letters in the alphabet are listed below:

• A: General Works
• B: Philosophy, Psychology, and Religion
• C: Auxiliary Sciences of History
• D: History - General and Old World
• E: History - American and North American
• F: History - U.S. and South American
• G: Geography, Anthropology, and Recreation
• H: Social Sciences
• J: Political Science
• K: Law
• L: Education
• M: Music
• N: Fine Arts
• P: Language and Literature
• Q: Sciences
• R: Medicine
• S: Agriculture
• T: Technology
• U: Military Science
• V: Naval Science
• Z: History of Books, Library Science, and Bibliography

See the Library of Congress for a complete list of main classes and their subclasses.

How to Read LC Call Numbers

Subclasses of the LC main classes are represented by a second letter. The first D in the call number indicates that the book is a work of history. The second D indicates that it is a work of German history.

DD
534
.C35
1998

LC call numbers are read line-by-line as explained in the following table.

Line Number	Part	How to Read	Represents
1	First letter	In alphabetical order A, B, C, D, etc.	Main class
	Second letter	In alphabetical order BA, BB, BC,BD, etc.	Subclass
2	Number	As a whole number. 1, 2, 3, 45, 534, 2000, 2500, etc.	Further subclasses
3	Letter	In alphabetical order .C, .D, .E, etc.	Author's last name
	Decimal	Number-by-number .C22, .C34, .C35, .C357, etc.
4	Date	In chronological order 1995, 1998, 2000, etc.	Date published
	Volume	In numerical order 1, 2, 3, 4, etc.	Volume published

LC Call Number Shelf Order

LA before LB		2327 before 2328		. B before .C5		. 554 before .63		1987 before 1991
LA 2301 . M37	LB 2327 . M3	LB 2327 . P35	LB 2328 . B3	LB 2328 . B34	LB 2328 . C55	LB 2328 . C554 1982	LB 2328 . C63 1992	LB 2395 . C65 1987	LB 2395 . C65 1991
	. M before .P		. 3 before .34		. 55 before .554		2328 before 2395