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Call Numbers & Library of Congress Classification System: What is a Call Number?

Library of Congress Classification System

Most books in the Mendik Library are arranged by the Library of Congress Classification System. The system divides all knowledge into twenty-one basic classes, each identified by a single letter of the alphabet. Most of these alphabetical classes are further divided into more specific subclasses, identified by two-letter, or occasionally, three-letter combinations.

For example:

Class K - Law

Library of Congress Classification: Class K -- Law

·         Subclass K - Law in general. Comparative and uniform law. Jurisprudence

·         Subclass KB - Religious law in general. Comparative religious law. Jurisprudence

·         Subclass KBM - Jewish law

·         Subclass KBP - Islamic law

·         Subclass KBR - History of canon law

·         Subclass KBU - Law of the Roman Catholic Church. The Holy See

·         Subclasses - KD-KDK United Kingdom and Ireland

·         Subclass KDZ - America. North America

·         Subclass KE - Canada

·         Subclass KF - United States

·         Subclass KG - Latin America - Mexico and Central America - West Indies. Caribbean area

·         Subclass KH - South America

·         Subclasses KJ-KKZ - Europe

·         Subclasses KL-KWX - Asia and Eurasia, Africa, Pacific Area, and Antarctica

·         Subclass KZ - Law of nations




·       You can see the complete list of the Library of Congress call numbers:

What Is a Call Number?

A call number is like a house address. It tells you where an item is located in a library. Each title owned by a library has its own unique call number. 

Call numbers appear:

Call numbers are usually on the spine of a library item, so they can be easily read on book shelves. Sometimes, when a spine is too narrow, the call number will be on the book's cover.

Anatomy of a Library of Congress Call Number

Book title:           Learned Hand : the man and the judge.

Author:                Gunther, Gerald

Call number:      KF373.H29 G86 2011      

Let’s look at this call number to see how this classification system works:

KF   - letter line, describes general subject area; alphabetical order

373 – number line, narrows subject area; numerical order

.H29 – cutter line, further narrows subject area or specifies author;  alphabetical  then decimal order

G86 – 2nd cutter line (if present) also in alphabetical then decimal order

2011 – year of publication, numerical order

Symposia, meetings, etc. use the date of the meeting and not the date of publication in the call number.

Let’s look at this book in our catalog