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NYC School Librarian Guidebook: Dewey Decimal System

Resources to examine our inherent bias, promote personal awareness, and help us build collections for our students that reflect themselves and the world around them.

Dewey Decimal System

The Dewey Decimal System is almost universally used as the organizing protocol for all school and public libraries. The location skills the students learn in your school library are directly transferable. Even at the college level, where the Library of Congress system is used, students will have learned basic location skills in your school library that will then transfer to the college level.

The basic breakdown of the Dewey Decimal System is as follows:

000 Generalities 

100 Philosophy and Psychology

200 Religion

300 Social Sciences

400 Language 500 Natural Sciences and Mathematics

600 Applied Sciences and Technology

700 The Arts

800 Literature and Rhetoric

900 Geography and History 

Dewey Decimal Resouces

Sears Subject Headings

Libraries must follow an authority in determining subject headings in order to maintain the integrity of the catalog. Most libraries commonly use either Library of Congress Subject Headings or Sears List of Subject Headings as the authoritative source of subject headings. Generally, schools use Sears. Sears offers a controlled vocabulary so that all books on the same subject are accessible through the same words. Main headings may be subdivided by: topic, aspects of a topic, geography, and chronology. Every subject heading in Sears is linked to the corresponding Dewey number.

Typically, librarians with both print and electronic catalogs offer both “see” and “see also” references to help patrons refine their search and find additional resources. If you are automated, request both types of headings in the MARC records, but activate the Sears headings only. 

Frequently Asked Questions about Sears Subject Headings


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