Dewey Decimal Classification

The Dewey Decimal Classification (DDC) is a numerical classification system used in many library catalogs (see article in Wikipedia). The classification is not a free resource, but copyrighted by the Online Computer Library Center (OCLC) since 1988.

Update by Robert: http://dewey.info/ provides linked DDC, under CC license.--Ulla 19:54, 24 August 2009 (UTC)

Resources

 * About Dewey Decimal Classification (DDC) (by OCLC)
 * An overview on the first three levels is available in Wikipedia (= DDC 22 Summaries)
 * DDC 22 Summaries can be downloaded and used via OCLC ResearchWorks after accepting the terms and conditions (T&C), see http://www.oclc.org/research/researchworks/ddc/terms.htm
 * Further DDC services (e.g. print copy, access to WebDewey) need to be licensed. The pricing can be found at: http://www.oclc.org/support/forms/pdf/dfwpro.pdf