top of page

Chapter 14. Dewey Decimal Classification

Chapter Outline

  • History

  • Publication of the Classification

  • Revision

  • Basic Principles

  • Notation Symbols

  • Evaluation

  • Assigning Call Numbers

  • Class Numbers

  • Number Building: Full Edition

  • Number Building: Abridged Edition

  • Item or Book Numbers

Key Takeaways

Chapter 14 covers the Dewey Decimal Classification (DDC) system, a widely used classification worldwide and by the majority of public libraries in the USA. DDC has been translated into several languages and is continually maintained, which is guided by an advisory body, the DDC Editorial Policy Committee (EPC), a ten-member international joint committee of OCLC and ALA, representing the users of the DDC. 

Decimal

The Dewey Decimal Classification system divides the universe of knowledge into the top ten classes and continues with a division into ten subclasses for the top three levels. This structure can be seen in the DDC Outline of the three summaries:  First summary - 10 main classes; Second summary - 100 divisions; Third summary - 1000 sections.

​

The DDC notation is purely numerical. At a minimum, a class number consists of three digits, with the possibility for expansion using a "dot" after the first three digits. 

Enumeration and Synthesis

The main classes in DDC are hierarchical in structure. Each level is divided on a base of ten — because of the notational system — and is subordinate to the level above it. This hierarchical structure progresses from the general to the specific.

​

Although the system was initially developed as an enumerative system, the introduction of the table for geographic subdivisions in the 17th edition and additional tables in the 18th edition provide numbers for commonly occurring subtopics or aspects that may be used with base numbers representing main topics throughout the schedules.  Currently, there are six tables of notation that can be added to class numbers. This allows for number building to provide more specificity and an additional level of synthesis in the DDC system.

Classification by Discipline

In many general bibliographic classification systems, the division of main classes and subclasses is based on academic disciplines, or fields of study, rather than on subjects. Such division means that the same subject may be classed under more than one class of the same scheme. In DDC, knowledge was initially divided into ten main classes that mirrored the academic divisions of Dewey’s time: General works, Philosophy, Theology, Sociology (later Social sciences), Philology, Natural science, Useful arts, Fine arts, Literature, and History. This makes the structure somewhat uneven as far as matching the world today and not reflective of the varied advancements of knowledge in different fields.

Number building

The DDC system allows for the expression of more complex topics through different methods of number building or synthesis. These methods include the use of Standard Subdivisions (Table 1); instructions to add to a base number, numbers from other parts of the classification systems; instructions to add numbers from 001-999 to the base number, in other words, another class number from the entire schedule; and additions to a base number from the auxiliary Tables 2-6 via a Table 1 instruction or via an instruction from the schedule.

Chapter References/Notes

  1. Dewey, M., & Mitchell, J. S. (2011). Dewey decimal classification and relative index (Ed. 23). Dublin, OH: OCLC, Online Computer Library Center, Inc. (p. xxxix).

  2. Maltby, A. (1975). Sayers’ manual of classification for librarians (5th ed.). London, UK: Andre Deutsch (p. 121). [Note: John Phillip Comaromi, on the other hand, argued that Hegel provided the philosophic underpinnings of Harris’s and Dewey’s classification systems.] [Comaromi, J. P. (1976). The eighteen editions of the Dewey decimal classification. Albany, NY: Forest Press Division, Lake Placid Education Foundation (p. 29).]

  3. Dewey, M., & Mitchell, J. S. (2012). Abridged Dewey decimal classification and relative index (Ed. 15). Dublin, OH: OCLC, Online Computer Library Center, Inc.

  4. OCLC, Online Computer Library Center. (2011). Webdewey [Subscription service]. Available from www.dewey.org/webdewey/

  5. Dewey, M. (2011). Introduction. In Dewey, M., & Mitchell, J. S. (2011). Dewey decimal classification and relative index (Ed. 23) (pp. xli–xlv). Dublin, OH: OCLC, Online Computer Library Center, Inc.

  6. Dewey, M. (2012). Introduction. In Dewey, M., & Mitchell, J. S. (2012). Abridged Dewey decimal classification and relative index (Ed. 15) (pp. xxxix–liv). Dublin, OH: OCLC, Online Computer Library Cen- ter, Inc.

  7. Cutter, C. A., Swanson, P. K., & Swift, E. M. (1969). C. A. Cutter’s two-figure author table (Swanson-Swift revision). Chicopee, MA: H. R. Huntting Company.

  8. Cutter, C. A., Swanson, P. K., & Swift, E. M. (1969). C. A. Cutter’s three-figure author table (Swanson- Swift revision). Chicopee, MA: H. R. Huntting Company.

  9. Cutter, C. A., Jones, K. E., Swanson, P. K., & Swift, E. M. (1969). Cutter-Sanborn three-figure author table (Swanson-Swift revision). Chicopee, MA: H. R. Huntting Company.

  10. OCLC, Online Computer Library Center. (2014). Dewey Cutter program [Software program]. Available from http://www.oclc.org/support/services/dewey/program.en.html

  11. See also: Comaromi, J. P. (1981). Book numbers: A historical study and practical guide to their use. Littleton, CO: Libraries Unlimited.

  12. Lehnus, D. J. (1980). Book numbers: History, principles, and application. Chicago, IL: American Library Association.

 

Additional Readings

Here, you will find readings specific to the contents of this chapter.

You may find more readings about similar topics on the Cataloging and Classification Web Resources page

Dewey Decimal Classification

​

Cutter Tables
bottom of page