Classification Systems

There are two basic ways to classify books in a library system.  Which system a library will use depends on the size and what the library is primarily used for.  Once you are able to understand the classification system, the easier it will be to find what you need.  The two classification systems used in libraries are the Dewey Decimal System and the Library of Congress System.

Dewey Decimal Classification System

            The Dewey Decimal System is named after a man named Melvil Dewey, and he was the first to come up with a classification system.  Some of the basics of the Dewey System are that it is divided into 10 major groups by numbers and is also used in the Powers Library!  The books that use the Dewey System at Powers are all non-fiction materials that are found with reference materials.  The call numbers are then arranged from lowest to highest; if the numbers are the same then they are arranged by the first three letters of the author’s last name.  Below are the classification groups:

            001-099           General Works             500-599           Natural Science

            100-199           Philosophy                    600-699           Applied Science

            200-299           Religion                        700-799           Fine Arts

            300-399           Social Science              800-899           Literature

            400-499           Languages                    900-999           Geography & History

The ten groups are then divided ever farther into their subject areas.  An example can be found below:

800-899           Literature

            800-809           Literature (general)       850-859           Italian, Romanian literature

            810-819           American literature        860-869           Spanish, Portuguese literature

            820-829           English & Old Eng.       870-879           Latin literature

            830-839           Germanic Lang. Lit.      880-889           Greek literature

            840-849           Romance Lang. Lit.      890-899           Other world literatures

The sections will keep breaking down into different categories as well so that the groups are very specific to the subject area, which makes finding a book easier!

Example of a Non-Fiction book call number:   

810.9---> Dewey Number

                                                            RAN ---> 1^st 3 letters of the author’s last name

Library of Congress Classification System

            The Library of Congress Classification System is set up for libraries that have over 200,000 volumes, which of course is not our library here at Powers High School.  We do not use this system but college libraries and some public libraries use this system.  This system is made up of 26 different categories and is categorized by letters.  Below are the 26 major groups:

            A         General Works                                       M         Music

            B          Philosophy, Psychology & Religion          N         Fine Arts

            C          Auxiliary Sciences of History                  P          Languages and Literatures

            D         History, Europe, Asia & Africa               Q         Science

            E-F       History, America (Western Hemisphere) R          Medicine

            G          Geography                                             S          Agriculture

            H         Social Sciences                                       T          Technology

            J           Political Science                                     U         Military Science

            K         Law                                                      V         Naval Science

            L          Education                                              Z          Library Science

These are then broken down even farther, just like in the Dewey System.  Below is a comparison of call numbers from the Library of Congress and Dewey for the same book, The Encyclopedia of Hollywood:

Dewey                                     Library of Congress                 

            384.809794                             PN

            SIE                                          1993.5

                                                            .U6S494

                                                            1990