How to Understand the Dewey Decimal System

The Dewey Decimal System, used in most libraries in the United States and Canada, allows for nonfiction books to be classified according to their subject matter and then grouped together on the shelves. This allows the librarian to place books in specific areas and for you to easily find the book you need. Read on to learn how to understand the Dewey Decimal System.

Instructions

Difficulty: Easy

1. Choose a book or a subject to look for in a library since using the Dewey Decimal System is the easiest way to understand it.
2. Verify that the book you are searching for is either nonfiction or considered literature. Literature is classified as books written by great authors and considered to be of value in the study of writing.
3. Work to determine the 3-digit number that classifies all nonfiction books within the Dewey Decimal System.
4. Determine which of the following broad categories the book or subject falls into: Generalities (000s), Philosophy and Psychology (100s), Religion (200s), Social Sciences (300s), Language (400s), Natural Sciences and Mathematics (500s), Technology/Applied Sciences (600s), Arts (700s), Literature and Rhetoric (800s) or Geography and History (900s).
5. Understand that every nonfiction book can be grouped into one of the broad categories and then further grouped by the more specific topic. So a book that is about physics will be in the 530s and book about chemistry will be in the 540s.
6. Clarify the more specific subject of your search, such as the periodic table of elements which is a more specific classification within the area of chemistry. All books dealing with this topic will be grouped together with the number 546.

Tips & Warnings

• The Dewey Decimal System is updated four times a year in order to accommodate new topics that are created.
• The three digits of the Dewey Decimal System classification are only the first part of the call number of a book. The three digits are followed by the first one, two or three letters of the author's last name. This is sometimes followed by the year of publication.
• The Library of Congress and academic and research libraries use The Library of Congress Classification System. Be careful to keep this in mind when visiting different types of libraries.