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How to Navigate the Library

This guide provides an introduction to library resources and how to find, evaluate, use, and cite them.

Call Numbers

SC4 Library uses the Library of Congress (LC) classification system, which uses a combination of letters and numbers (call numbers) to arrange the books.

The LC system is one of the most widely used classification systems in the world, and it is conducive to browsing as books of the same topic are generally shelved together.

Below you can see how the LC system's call numbers work, if you were to look at a shelf of books.


call number explanation

Call Number Breakdown

Now that you know how LC call numbers are arranged, let's look at a further breakdown of a call number.

Our example call number is PR6029.R8 N49 2015, which is for the novel 1984 by George Orwell.


PR     Call numbers begin with one or more letters and are based on the general subject area

PR is the classification for English Literature

Arranged on the shelf in alphabetical order


6029  The second line is a whole number that indicates a more specific subject area

6029 falls under the Drama subclass

Arranged on the shelf in numerical order within the PR section


.R8      The third line is a combination of letters and numbers that usually represent the author's last name

This number should be read as a decimal. (.R8 comes before .W6)

Arranged on the shelf in alphabetical then decimal order


N49    The fourth line is a second combination of letters and numbers to further refine

 Can indicate a further subtopic, an author/artist, language, geographic region, etc.

 These numbers are not always present; some call numbers will not contain a fourth line


2015   Publication date 

 Arranged chronologically on the shelf



The online catalog image for this book is shown below.

1984 call number in online catalog


1. The call number - This indicates where the book is on the shelf

2. The collection - This indicates where the book is in the library.

At SC4 Library, the "Circulating Books" collection refers to the majority of the books in our moveable stacks.

3. The item status - This indicates whether the book is checked in, checked out, missing, etc.

4. The location - St. Clair County Community College


Other collections and their locations
Equipment - These are items such as telescopes, health sciences anatomical models, laptops, games, and other non-book items the library loans. They are generally kept behind the circulation desk.
Index - These are volumes that provide references and direction to periodical articles or books by subject, author, or other criteria. The index section is aisle 57 in the circulating books moveable stacks.
Oversized - These are large volumes that do not fit on our standard shelves. They are located in aisles 55 and 56 in the circulating books moveable stacks.
Periodicals - These are magazines, newspapers, and/or  journals. The majority of periodicals can be found in our online databases, but the print periodicals the library does hold are on the periodicals shelf between the circulation desk and the library entrance.
Reference - These are volumes, such as encyclopedias, dictionaries, atlases, etc., that stay in library and do not circulate. These books are in the reference section of the library.
Reserve   These are books or items set aside for specific courses, providing access only to students in that course. These are generally kept behind the circulation desk.


There are several other collection designations at SC4 Library. If you're not sure where a book or other item is located, please ask a librarian!


Library of Congress Classification

The chart below is a basic overview of the Library of Congress Classifications.


With the Library of Congress system, books of similar topics are placed together on the shelves, which is more conducive to browsing. You may use OneSearch or the library catalog to find a particular book and go to the shelves to retrieve it, only to find a potentially much better book for your subject on the shelf next to the one you had originally found.


library of congress classification system


For more information on the LC system, visit the Library of Congress' website.


Image: " English: An Infographic detailing the various disciplines covered by the Library of Congress Classification System." Wikimedia, 14 May 2015, This file is licensed under the Creative Commons Attribution 4.0 International license.

Your Librarian

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Jane Lewandoski
Phone (810) 989-5640
Text (810) 515-7343