Northern Kentucky University

The Library of Congress serves as the research arm of the United States Congress. It is also recognized as the national library for the United States. The Library of Congress is the largest library in the world and works cooperatively with other libraries worldwide.

Many research libraries, including Steely Library, have adopted the systems used by the Library of Congress for organizing their materials. When using Steely Library and searching NKUIRE, the library catalog, two of these organizational systems will be obvious. These are the Library of Congress Classification (LCC) and the Library of Congress Subject Headings (LCSH).

Library of Congress Classification

The Library of Congress Classification (LCC) system is used to assign a unique call number to each item in the collection. Items are arranged on the library shelves by their call numbers, thus it is necessary to know an item's call number in order to find it on the shelves. With the LCC system, all call numbers begin with at least one letter of the alphabet. Each letter stands for a broad subject area:

Letter Subject area

After assigning an item to a broad subject area, a series of letter-number codes are assigned to each item in order to create a unique call number for the item. The first line of the call number is always the letter(s) representing the general subject of the item as outlined in the table. To what subject area have these books been assigned?

A call number is an "address" for an item in the library collection. In the Steely Library catalog, call numbers are written horizontally (LB 2331 .N43 1989) and should be read from left to right.

Call numbers on the spines of books are usually vertical, as seen in the example, and should be read from top to bottom.

Sometimes a call number will have an extra line on top that consists of a word or abbreviation. This line is usually used for providing location information. It tells you on what floor or in what area of the library the item is located.

Here is a listing of the location abbreviations used by Steely Library:

Chase

Chase Law Library, Nunn Hall

Gov Docs

Government Documents, third floor, Steely

Ky Collection

Special Collections & Archives, first floor, Steely

LRC

Learning Resource Collection, fourth floor, Steely

Maps

Government Documents, third floor Steely

MF or MIC

Periodicals/Serials, fourth floor, Steely

Oversize

First floor, after the "Z" books

Ref

Reference area, third floor, Steely

Reserve

Third floor Public Service Desk, Steely

LT

Learning Resource Collection, fourth floor, Steely

Y

Learning Resource Collection, fourth floor, Steely

Library of Congress Subject Headings

The Library of Congress Subject Headings (LCSH) is a gigantic listing of all the terms used by the Library of Congress to describe the items in their collection. Just as with the LCC, many libraries around the world, including Steely Library, use this list for describing their collections. In print version, the LCSH currently comprises five very thick volumes. For many years, the print version of the LCSH has been bound with red covers. Because of that, they are often referred to as the "red books." Only since about 2009 has the LCSH been available online (http://id.loc.gov/search/).

Subject headings facilitate a user's ability to access relevant materials listed in the library catalog that pertain to the topic of interest. As an example, you are writing a research paper about "chocolate." You want to find everything that the library owns that discusses some aspect of chocolate. When you search "chocolate" as a subject heading in the library catalog, you find a variety of items covering many different aspects about chocolate. There are items that discuss the health aspects of chocolate, the history, the chocolate industry, etc. Our subject search for chocolate was straightforward and very efficient. Unfortunately, subject searches aren't always this easy.

In some circles, the LCSH is considered a thesaurus. It provides a controlled vocabulary of subject terms that may be assigned to library materials. A characteristic of many thesauri is that once a term is included in the list it is practically set in stone and changing it is very difficult. This characteristic is true of the Library of Congress Subject Headings.

For example, only in recent years was the term "CD-ROM" included in the LCSH. Prior to its acceptance as a subject heading, it was necessary to search for "compact disc read-only memory" in order to find information about the technology. Because the LCSH is a controlled vocabulary of subject terms, it is slow to reflect the common terms used in society when discussing various topics.

Searching by subject heading is usually the most efficient way of finding relative materials about a certain topic. Unfortunately, it often is the most difficult way of searching for information about a topic. For additional information about subject searching, refer to the tutorial, Subject vs. Keyword Searching.