Think back to when you were in elementary or high school. Remember going to the library and being perplexed by all those numbers and letters on those stickers on the books? Maybe you asked your librarian where to find the books about dinosaurs, only to be totally confused when she answered, “567.9.” Here is a guide that will hopefully help you (or help you to teach your own children) to solve the mystery of the Dewey Decimal System.
Generally, the numbers of the Dewey Decimal System are applied to nonfiction books. Nonfiction books are those that are based on fact, and can also be known as informational books. They are divided loosely by topic and are categorized in groups by “hundreds.” The number refers to the classification number on the spine of the book and the shelf on which it is located, not to the number of books in its particular group.
A book may fall into one of ten groups of hundreds, from 000’s up to the 900’s, each with its own classification theme. Nonfiction books in libraries that use the Dewey Decimal system are shelved in numerical order based on this numbering system. Each group of hundreds has its own particular topic or theme. Each digit represents a narrowing of topic, with the digits following the decimal being the most specific. The more digits following the decimal, the more specific the classification of the book.
000’s: This group is usually known as Generalities. It often contains books that do not seem to fit into any other category, or those which could fit into multiple categories. Examples that a patron may find here include encyclopedias, books about libraries, and the Guinness Book of World Records.
100’s, Philosophy: Books in the 100’s often center on personal themes such as self-help. Dealing with issues like anger, difficult people, and bullying will usually be found in the 100’s.
200’s, Religion: Bibles, the Koran, religious stories, and most books about religious holidays such as Ramadan and Passover will usually be found in the 200’s.
300’s, Social Sciences and Government: The 300’s are perhaps the most varied section of the Dewey Decimal System. In it you will find themes varying from important government documents like the Constitution and Declaration of Independence to military branches to holidays to fairy tales. Students have often asked me in the past why fairy tales are shelved with the nonfiction books, since they are so obviously fiction stories. My standard answer has been that fairy tales usually have a cultural basis, therefore they fall under the category of social sciences.
400’s, Languages: Here is where you will find dictionaries and phrase books in various languages including sign language. Books on grammar and phonics and pronunciation guides will also be found in this section.
500’s, Natural Sciences: Basically, anything that occurs in the natural world will have books located in the 500’s. Caves, rocks, dinosaurs, electricity, plants, space, oceans, weather, and animals are just a few of the themes that patrons will find when browsing this usually large section of books.
600’s, Physical Sciences: The 600’s have seemingly become a bit of a catchall as the concepts of science and technology have changed drastically over the years. Here, patrons will find books with themes like medicine (including diseases), cars, motorcycles, cooking, spacecraft, and health.
700’s, Arts & Humanities: This section is usually a favorite among elementary students, as it contains the ever popular drawing books and books about all types of sports. Other themes located in the 700’s include music, architecture, dance, painting, crafts, and sculpture.
800’s, Poetry and Literature: The 800’s has primarily become a section for poetry and plays in most school libraries. When the Dewey Decimal System was first put into use, it was intended for fictional stories to be located in the 800’s as well, however most libraries choose to put fiction in its own separate section. Sometimes, story collections are located in the 800’s as well.
900’s, Geography and History: As with the 500’s, the 900’s is usually one of the largest groups in a library’s nonfiction collection. Located here are books about maps, states, countries, major wars, historical time periods, and some books about historical persons.
The Dewey Decimal System is an imprecise system that perplexes even librarians at times. If the preceding guide still has you confused about where to find the book you need, ask your local librarian (information or media specialist) for help. She or he will be able to tell you where to find your book, even if she/he may not be able to tell you why it’s located where it is!
