Dewey® Services

Resources for teachers and students of the DDC

If you work in a public or K–12 library—or use one—you may need information about the Dewey Decimal Classification (DDC) system rather than from it. These resources can help.

  • Looking for a brief introduction to the DDC system to help your users understand better how your library collection is organized? Our brief PowerPoint presentations—one for kids and one for adults—provide a quick, easy-to-understand look at the DDC, which libraries have used for 130 years to organize their collections.
  • The DDC 23 Introduction is a full reprint from volume 1 of DDC 23, which provides a detailed overview of the DDC, including basic terminology and an explanation of DDC structure, complete with many helpful examples. If you are new to classifying with Dewey, this introduction will help you get started quickly.
  • The Glossary is also reprinted from volume 1 of DDC 23, and it provides helpful definitions of DDC terms and gives users a common language for implementing the DDC.
  • If you need a high-level view of the DDC structure, the DDC Summaries are the best place to look.
  • Want to know more about Melvil Dewey, founder of the DDC?
  • Visit the Dewey blog for news and views on classification issues, interesting and unusual DDC resources and a means to provide ongoing feedback to help shape the DDC's future.

The Dewey Decimal Classification (DDC) system is the world’s most widely used way to organize library collections. The DDC constantly updates to enable better discovery across any topic in multiple languages. Because the DDC is easy to use, you can increase the visibility of your materials quickly and efficiently.

Service availability

  • Available everywhere

Learn more

Download the Dewey Services brochure

Download the Dewey Services brochure
Download the brochure (US Letter)
Download the brochure (A4)

Connect with English-language WebDewey users in the OCLC Community Center.

Upcoming events

Watch this space for more upcoming webinars

On-demand webinars

Watch this space for past and recorded Dewey Services events.

See all Dewey services events »

Recent news

The Dewey blog is a great source for news and views on classification issues as well as interesting and unusual DDC resources and curiosities. It's also a convenient way to share feedback directly to the DDC editors to help shape the future of the DDC.

All copyright rights in the Dewey Decimal Classification system are owned by OCLC, Inc. Dewey, Dewey Decimal Classification, OCLC and WebDewey are registered trademarks of OCLC, Inc.