Library Classification Systems
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Libraries use classification systems to organize library materials so they can be easily and quickly found. These systems place items about the same subject in the same area of the library. Two systems commonly used in the United States are the Library of Congress Classification (LC) system, and the Dewey Decimal Classification (DDC) system.
The Library of Congress Classification system is used in most college and university libraries. In the Sherratt Library, the LC system is used in all collections except the Curriculum and Juvenile Collections on the Third floor, which use the Dewey Decimal Classification System. The DDC is used in school, public, and small libraries.
In 1899, the United States Library of Congress created a classification scheme for books. It is called the Library of Congress Classification system (LC for short). In this system, all knowledge is divided into 21 broad subject areas by letters of the alphabet (I, O, W, X, and Y are not used). There is no significance for the letters of the alphabet chosen for each broad subject area. There is no need to memorize this classification system, but it is helpful to know how it works so that you can quickly find books.
Here's an outline of the major subject areas in the LC system:
A - General Works - encyclopedias M - Music B - Philosophy, Psychology, Religion N - Fine Arts C - History - Auxiliary Sciences P - Language and Literature D - History (except American) Q - Science E - General U.S. History R - Medicine F - Local U.S. History S - Agriculture G - Geography, Anthropology, Recreation T- Technology H - Social Sciences U - Military J - Political Science V - Naval Science K - Law Z - Bibliography and Library Science L - Education
Each subject subdivision is then further divided into specific topics using numbers. This combination of subject areas (letters) and numbers is called the call number for that book.
The Sherratt Library assigns each library item a unique call number according to the Library of Congress Classification system. The call number is a unique "address" for that item. You need this call number to find a book in the library. The call number is available from the library catalog, and is printed on the spine or cover of each book.
A call number begins with one or two letters. The call number for the book shown here is:
GV 989 .A52
Books are placed on the shelves according to these call numbers. Books are shelved from left to right according to the LC system. Books are arranged first by the alphabetical top row, then by the number in the second row, finally by the alphabetical letter and decimal number in the third row:
Remember, when using decimal numbers, numbers will be smaller to larger, left to right! (For example, when comparing .A4010 with .A52 by position, the 4 is smaller than 5 so .A4010 comes first.)
If you understand how the LC system works in the Sherratt Library, you'll be able to walk into the Marriott Library at the University of Utah, or the Harold B. Lee Library at Brigham Young University, or the Widener Library at Harvard University and find books!
Collection codes are identifiers added at the beginning of the call number to indicate a particular collection:
Code Collection Location Curr Curriculum Collection Garden IM Instructional Media Garden Juv Juvenile Collection 3rd Oversize Main - Oversize 3rd Ref Reference Collection 1st SpColl Special Collections Garden
When you've found a book in the library catalog, be sure to note:
With this information, you can go to that collection, and to the shelf where it is located.
For example, suppose you want to find the book Roughing It, written by Mark Twain. It is in the Main Collection on the Second floor, call number
PS 1318 .A1
As you move through the book shelves, check the signs on the wooden ends of the shelves. Notice that the call number falls within the range of the shelf in this picture.
As you go down this aisle, look at the spine labels on the books. You see there are several books labeled PS 1318. Then look for the .A1 portion of the call number. Notice that there are other books on this shelf authored by Mark Twain.
TIP: Once you find an item on the shelf, browse items nearby. Books are shelved according to subject, so you may find something useful.
If the library catalog Copy Status indicates that an item is "Checked In" but you cannot find it on the shelf, follow these steps:
Hint: When you take an item off the shelf, don't try to put it back yourself. Instead, put it on a red shelf so that a librarian can make sure it is returned to its correct location.
As a student at SUU, you can use your SUU ID to borrow books from other academic libraries in Utah. Before you go to another library, you should know there is a library catalog that lets you search any or all of the academic libraries in Utah - it's called Utah's
The Dewey Decimal Classification system is used for the Curriculum and Juvenile Collections. These book collections are used mainly by education students. This system uses numbers to group books by subject:
Dewey Decimal Classification System
000 - Generalities (e.g., encyclopedias)
100 - Philosophy and Psychology
200 - Religion
300 - Social Sciences
400 - Language
500 - Natural Sciences and Mathematics
600 - Technology (Applied Sciences and Medicine)
700 - Arts, Entertainment, and Sports
800 - Literature and Rhetoric
900 - Geography and History