LIBRARY BASICS: Organization of Library Materials


Organization of Library Materials

Library of Congress Classification Schedule (Call Numbers)

Library materials are organized in a classified system. Most academic libraries organize their materials using the Library of Congress (LC) classification. The LC system organizes materials according to subject. Examples of subject classification are: fine arts and architecture are classified in the N classification; education in the L classification; women's studies in the HQ classification; music in the M classification; and literature and language in the P classification.

Within each of these divisions, the organization of the classification varies according to the subject. An example of this can be seen in the comparison of the P (literature and language) and N (fine arts and architecture) classifications. Within the P classification for literature, each author has a call number area. All an author's fictional works, including short stories, plays, novels, are shelved in that call number area, followed by criticism and bibliographies about the author. With this organizational scheme, you may browse the fictional works of an author, but you cannot browse a section of plays. Within the N classification, the divisions are visual art, architecture, sculpture, drawing, painting, printmaking, design, and the arts in general. You may browse a section by medium, but you cannot browse all the books about one artist. Books on Picasso are classified according to the subject, with the books on painting in the ND classification, prints in the NE classification, and ceramics in the NK classification. An LC call number allows an item to be cataloged to a very specific subject area by using a combination of numbers and letters and ending with a date of publication.

LC Classification Example

Jones, Amelia.  Body Art/Performing the Subject.  Minneapolis: University of Minnesota Press, 1998.

N                     Visual Arts

6494                History – Modern Art – 20th Century

.B63                Special Aspects – Body art

J66                  Cutter number for author (Jones)

1998                Publication Date

Controlled Vocabularies

Bibliographic records for library materials are also assigned subject terms or phrases according to their subject. These terms are usually compiled in a formal listing such as book, thesaurus, or electronic index. Controlled vocabularies include the Library of Congress Subject Headings and subject thesauri. These controlled vocabularies usually have one of three formats: (1) Library of Congress Subject Headings; (2) descriptors; and (3) a combined format specific to a database/index. Many electronic products offer an online thesaurus or index of the controlled vocabulary.

Library of Congress Subject Headings

The Library of Congress subject headings (LCSH) are assigned to bibliographic records of whole item materials such as books, videos, manuscripts, etc. The first subject heading assigned to a book or other item is directly related to the call number given to that book.  These subject headings are hierarchical, with main headings followed by subheadings. Some generic subheadings can be applied at the end of most main LC subject heading, including history, biography, pictorial works, and description and travel. In searching most databases, a LC subject heading must be entered in the search field letter by letter and word for word in order to retrieve records on the subject.  LC subject headings are used in library online catalogs and WorldCat, a FirstSearch database. The Library of Congress Subject Headings volumes are available at several Libraries locations, including the Ready Reference section behind the Arts and Humanities Reference Desk (Z695.U4749).  The Library of Congress Subject Headings volumes offer a key to their usage at the beginning of each volume and the LC subject headings are listed in bold.  In addition, relational terms are also listed in conjunction with the following abbreviations:

LC subject headings are usually plural, but may be singular. An example of each type would be the headings for paintings and painting. In the plural form, paintings represents the actual fine art object.  In the singular form, painting represents the action of painting.

If you do not know the exact subject heading for your topic, search the database by keyword.  In the bibliographic record, find the assigned subject heading(s).  Reenter your search using the correct heading as a subject search.  In the online catalog and WorldCat, subject headings will be hot linked.

Library of Congress Subject Headings Example

Prints (May Subd Geog)

UF       Fine prints

BT       Graphic arts

-           19th century (May Subd Geog)

--         Japanese influences

Use Prints - Japanese influences


--         Italy

EX:  Prints - Competitions - Italy


Descriptors are another example of a controlled vocabulary.  Bibliographic records in some subject indexes and abstracts are assigned descriptors.  Descriptors are non-hierarchical and more flexible.  They can be used individually or in combination to locate materials on a subject.  The descriptors are listed in a thesaurus or index.  Descriptors are used in numerous databases, including ERIC, PsycINFO, and Sociological Abstracts.

Combined Format Headings

Some databases do not use the Library of Congress subject headings or the more simplified descriptor format. Instead a combined format is used. This combined format mimics the LC subject headings, but does not comply completely with that system. These headings can be found in several databases, including Art Index, Humanities Index, and the MLA Bibliography.

Practice Activities:

1. Go to the Library of Congress classification schedule, click here. Identify the call number range for the following subjects:   1. Mural Painting;   2. Women, Feminism

2. Consult the Library of Congress Subject Heading volumes or the The CAT.  Locate two LC subject headings on your topic. You may begin by using keywords.