Dewey Decimal System

Dewey Decimal System
Name	Dewey Decimal Classification
Creator	Melvil Dewey
Released	0 1876
Latest release	23 (2023)
Classification	Discipline-based, hierarchical
Related	Universal Decimal Classification
Used by	Over 200,000 libraries in 135+ countries

Dewey Decimal System. The Dewey Decimal Classification (DDC) is a proprietary library classification system first published in the United States by Melvil Dewey in 1876. It revolutionized library science by organizing knowledge into a numerical, hierarchical structure, enabling efficient shelf arrangement and subject access. This system has been translated into over thirty languages and remains the world's most widely used library classification.

Overview and History

The system was conceived by Melvil Dewey while working at the Amherst College library, with the first edition published in 1876. Dewey was influenced by earlier systems like the Baconian method and the work of William Torrey Harris, but sought a more practical solution for public libraries experiencing rapid growth. The classification's adoption was championed by the newly formed American Library Association and spread rapidly across North America and later to institutions like the British Library. Key developments in its history include the establishment of the Library of Congress as a distribution partner and the founding of the Forest Press to manage its publication.

Structure and Classification

The system organizes all knowledge into ten main classes, each assigned a hundred-number span. These broad categories include divisions for Philosophy, Religion, Social sciences, Language, Pure science, Technology, The arts, Literature, History, and Geography. Each class is further divided into ten divisions, and each division into ten sections, creating a detailed hierarchical structure. For example, within the 600s for Technology, Medicine is located at 610, and Engineering at 620. This structure allows for the co-location of related subjects, such as placing works on the American Civil War near those on Ulysses S. Grant and Robert E. Lee.

Notation and Call Numbers

The notation is purely Arabic numerals, using a decimal point to extend classification numbers for greater specificity. A typical call number consists of the DDC number, a Cutter number (often derived from the Cutter Expansive Classification), and sometimes a year of publication or volume indicator. This combination creates a unique identifier for each item, facilitating precise shelf location. The notation's simplicity allows for infinite theoretical subdivision; for instance, a work on Renaissance sculpture in Italy would have a longer, more specific number than a general work on European art.

Use in Libraries

Libraries worldwide, from the Library of Congress to small public library branches, use the system to arrange physical collections on shelves in a logical, subject-based order. It is integral to online public access catalog (OPAC) systems, where the classification number serves as a key search and browsing parameter. The system's widespread use facilitates interlibrary loan and resource sharing among institutions like the New York Public Library and the University of Oxford libraries. Its adaptability allows it to be applied in diverse settings, including school libraries and specialized collections.

Editions and Maintenance

The system is currently owned by OCLC (Online Computer Library Center) and is under the continuous editorial control of the Decimal Classification Editorial Policy Committee (EPC). Major full editions are published approximately every seven years, with the 23rd edition released in 2023. Between editions, updates are disseminated through the electronic version, WebDewey, and publication of DDC Summaries. The editorial process involves international consultation to address new topics, such as those related to artificial intelligence or climate change, ensuring the system remains current.

Comparison with Other Systems

The primary alternative is the Library of Congress Classification (LCC), developed for the massive collection of the Library of Congress and used by most large academic and research libraries in the United States. Globally, the Universal Decimal Classification (UDC), an adaptation of the DDC, is prevalent in Europe and for specialized collections. Other systems include the Bliss bibliographic classification and the Colon classification developed by S. R. Ranganathan. Each system has philosophical differences; for instance, LCC is more enumerative and discipline-oriented, while the DDC's decimal structure offers a different approach to hierarchy and mnemonics.

Category:Library classification systems Category:1876 introductions