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Finding Books

Finding guide for library materials

How to Read a Call Number

Books at Pratt are organized using the Dewey Decimal System; if you are searching the stacks for a book, be sure to make note of the call number listed in the library catalog. But how do you make sense of all these numbers and letters? This page from our Pratt Library How-To Guide Zine illustrates how to read a call number:

  • Before the decimal, books are organized in ascending numerical order from 000-999.
  • Books are also organized in ascending order after the decimal; for instance, a book with the call number 700 (no decimal) would precede 700.01, with 700.10 further along the shelf.
  • After the number sequence, a letter and number sequence should be first read alphabetically, then numerically in ascending order. So 700.01 A123 would precede 700.01 B231.

This graphic illustrates parts of the Dewey Decimal call number, like the main class, division, section, and classification.

The HowCast video below succinctly explains Dewey Decimal call numbers:

Main Classes in Dewey Decimal System

Dewey Decimal call numbers are organized as follows:

  • The three numbers before the decimal are the Main Class, organized by the subject of the book.
  • The numbers following the decimal are subdivisions of the main class, organized further by subject and author.

The chart below includes all of the main classes in the Dewey Decimal System.

Call Number Subject
000-099 Computer Science, Information, General Knowledge
100-199 Philosophy and Psychology
200-299 Religion
300-399 Social Science
400-499 Languages
500-599 Sciences (including Math)
600-699 Technology
700-799 Arts and Recreation
800-899 Literature
900-999 History and Geography

A breakdown of further subdivisions can be found on the OCLC website.

Popular Call Numbers

While students at Pratt Institute have a wide variety interests - research and otherwise - the following some of Pratt's most popular call numbers:

Discipline Sub Category Call Number Floor In Stacks
Architecture   720 1M
Art History   709 1M
Art Ceramics 738 1M
  Decorative Arts 745 1M
  Film 791.43 2
  Painting 750 2
  Textiles 746 2
  Sculpture 731 1M
Fashion Design 391 1
  Costume Making 646.4 1
Interior Design   749 2