What’s The Difference Between Dewey Decimal and Library of Congress?
The two major classification systems in libraries are described.
Both systems organize material based on disciplines (or classes of knowledge), both use a controlled vocabulary, and both are regularly revised to stay responsive to the changing information landscape.
But the systems do have notable differences; each system is briefly described below, followed by a comparison of the two.
Dewey Decimal Classification (DDC)
Developed in 1876 by Melvil Dewey, the Dewey Decimal Classification (DDC) system has served libraries for over a century and is the most commonly used library classification.
DDC is based on ten major classes, each of which represents a different discipline. Each class is then subdivided into ten subdivisions, which are then further divided depending on the specificity.
Library of Congress Classification (LCC)
Developed in the early 1900s, the Library of Congress Classification (LCC) has been in use for almost as long as DDC; this system was designed primarily to serve the information needs of Congress, and secondarily to serve the needs of other government agencies and scholars.
LCC is based on 21 major classes, each of which represents a different discipline. Each class is then subdivided into subclasses, each of which may have a different arrangement or a different number of further subdivisions.
Comparison of DDC to LCC
* DDC is used in most public and school libraries; LCC is used in most academic and special libraries.
* The DDC only uses numbers; LCC uses both letters and numbers.
* DDC has classifications for fiction and poetry; LCC does not.
* DDC is more of a closed system—because all of the numbers have been assigned, the system cannot be expanded for new disciplines. The LCC system allows for more classifications.
* DDC follows a hierarchical pattern that uses consistent sub-divisions. For example, the sub-division 03 is for dictionaries and encyclopedias, so dictionaries and encyclopedias related to food and drink are 641.03 and dictionaries and encyclopedias related to buildings and construction are 690.03. In contrast, LCC sub-classifications do not follow a consistency across sub-divisions.
* Critics have noted that both systems place a heavy emphasis on American and European cultures at the expense of other cultures.
Battles, M. (2004). Library: An unquiet history. New York: W. W. Norton & Co.
Rubin, R. E. (2004). Foundations of library science, 2nd ed. New York: Neal-Schuman.