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Monthly Spotlight: Dewey Decimal

Dewey Decimal System Day

What is it?

Dewey Decimal Classification is a system for organizing the contents of a library based on the division of all knowledge into 10 groups, with each group assigned 100 numbers.

The 10 main groups are:

  • 000–099, general works;
  • 100–199, philosophy and psychology;
  • 200–299, religion;
  • 300–399, social sciences;
  • 400–499, language;
  • 500–599, natural sciences and mathematics;
  • 600–699, technology;
  • 700–799, the arts;
  • 800–899, literature and rhetoric;
  • 900–999, history, biography, and geography.

These 10 main groups are in turn subdivided again and again to provide more specific subject groups.

How to Use It

Start with the area of interest. What section are they in? History? Travel? Religion?

     This will be the 100s number before the decimal. (600= Technology (Applied Sciences)

What subgenre is the interest? If you're looking into technology in applied sciences, is it agriculture? Animal Husbandry? 

     This will be the 10s number. 600= Technology (Applied Sciences)/630=Agriculture and Related Tech/636= Animal Husbandry

Next will be the subdivisions. Do you want to learn more about cats? Dogs? Birds?

       This will be your decimal. 636.7=Dogs/636.8 Cats

For more information about Dewey Classifications and its history, check out this packet from the Online Computer Library Center (OCLC).

Quick Look

The Ten Main Classes

  • 000 Computer science, information & general works
  • 100 Philosophy & psychology
  • 200 Religion
  • 300 Social sciences
  • 400 Language
  • 500 Science
  • 600 Technology
  • 700 Arts & Recreation
  • 800 Literature
  • 900 History & geography

The Hundred Divisions

  • 010,020,030,040...
    • Subgenres/more specific categories that fall under the larger areas. 
      • bibliographies, Library & Information Sciences, Encyclopedias, etc.

The Thousand Sections

  • 001, 002, 003, 004...
    • Specific Subgenres/even smaller sections, which are even more specific.
      • systems, data processing, computer programming, etc.

For a full summary on specific genres and Dewey Decimals, check out this summary from the Online Computer Library Center. 

Peosta Library

The Peosta Campus Library has 2 libraries in 1 and is in 4 different sections, all of which are organized via the Dewey Decimal System. The front of the library has children's books, audiobooks, new materials, and our library of things. Along the fireplace and the sleepytime room, you can find our magazines and journals. In the back of the library will be the main stacks and posters identifying which Dewey numbers are held on each set of shelves. Lastly, there is a small study space before the individual study rooms that hosts our new Assignment Center, which holds more books and posters for help with your assignments.

The NICC books will have a white label, and the Dubuque County Library District (DCLD) has blue labels.

Your NICC student ID can be used for checkout on either of these collections.

Calmar Library

The Calmar Library has recently done some renovations and is now all on a single floor! The second floor of the Student Center is where you will find all the books and materials you will need to use to help you pass your classes or have a good time. Along the sides of the bookshelves will be the posters containing the Dewey Decimal Numbers for the books on their shelves.

All the books in this library are NICC-owned and can be checked out with your student ID.  

If you need help finding something or requesting material, feel free to ask a librarian at the circulation desk.

Fun Facts

  • Dewey Numbers are often called Call Numbers
  • The number before the decimal point is always treated as a whole number.
  • The numbers following the decimal point are treated as decimals.
  • It was made by Melvil Dewey for the Amherst College Library
    • And was based on W.T. Harris' classification for the St. Louis Public Library
  • The system was first used in 1873
    • and published in 1876
  • It is the most widely used classification system in the world
    • More than 135 countries use this classification
  • Dewey can also be used for other purposes, like a browsing mechanism for resources on the web
  • The system was updated and maintained by the Library of Congress
    • Here, they annually assign over 110,000 numbers to record for works cataloged in the library.

This information was gathered from Britannica, the University System of Georgia, and the Online Computer Library Center.