DEWEY? WE DO!

1. DEWEY? WE DO! Decoding the mysteries of the Dewey Decimal System.

2. SO MANY BOOKS!! HOW DO I FIND THE ONE I WANT? Think of a room full of books. They’re not in any order. Big ones and small ones, paperbacks and hardcovers, a book about dinosaurs next to a cookbook next to a dictionary. It might be fun to browse through a mess like that—but it would be almost impossible if there were one particular book you wanted to find.

3. In the late 1800s, a librarian named Melvil Dewey developed a way to organize books in a library so they’d be easier to find. There are lots of subjects books can be about. Some subjects have nothing in common—like wolves and cookbooks. Others are very similar—like flowers and trees. Dewey grouped all the similar subjects together. He settled on ten big groups of subjects. Then he assigned a number to those big subjects. This first basic classification looks like this:

4. 000 General KnowledgeAlmanacs, Encyclopedias, Libraries, Museums, Newspapers ... 100 Psychology and PhilosophyDeath & Dying, Ethics, Feelings, Logic, Making Friends, Optical Illusions, Superstitions ... 200 Religions and Mythology Amish, Bible Stories, Buddhism, Christianity, Judaism, Islam, Quakers, and other world religions; Greek, Roman and other myths... 300 Social Sciences and Folklore Careers, Customs, Environment, Families, Folktales, Government, Manners, Money, Recycling ... 400 Languages and GrammarChinese, English, French, German, Italian, Japanese, Sign Language, Spanish. Includes dictionaries. 500 Math and Science Animals, Biology, Chemistry, Dinosaurs, Fish, Geology, Insects, Physics, Planets, Plants ... 600 Medicine and Technology Computers, Cookbooks, Engineering, Farming, Health, Human Body, Inventions, Manufacturing, Nutrition ... 700 Arts & RecreationArchitecture, Crafts, Drawing, Games, Jokes, Music, Puppets, Songbooks, Sports ... 800 LiteratureChildren's Literature, Plays, Poetry, Shakespeare, Writing ... 900 Geography and History Biographies, Countries, Native Americans, States, Travel, Wars ...

5. Then Dewey broke the big subjects down into smaller subjects by dividing the big, “hundreds” numbers into smaller, “tens” numbers. Similar subjects were assigned numbers that were close together.

16. But even these divisions were not enough. For instance, Mr. Dewey assigned the number 980 to the continent of South America. But there are many countries in that big continent. The system Mr. Dewey designed was flexible enough to allow for a separate number for different countries and regions: 980 General history of South America 981 Brazil 982 Argentina 983 Chile 984 Bolivia 985 Peru 986 Colombia & Ecuador 987 Venezuela 988 Guiana 989 Paraguay & Uruguay

17. Mr. Dewey’s classification system allows librarians to divide the numbers that are used to describe subjects even further by using decimals—which is why we call it the Dewey DECIMAL System. For instance, 362 is the number assigned to social problems. But there are all sorts of problems in society. So the number is divided again: 362.1 Social aspects of health problems like AIDS 362.2 Social aspects of mental illness 362.4 Social aspects of physical disabilities like blindness 362.5 Poverty and homelessness 362.6 Social issues of the elderly 362.7 Social issues of children and teens 362.8 Social issues of families, including domestic violence 362.9 Military draft

18. Librarians can continue to create smaller and smaller divisions using the decimal numbers. For instance, 582.1 is the number for plants with seeds. But there are different kinds of plants with seeds, such as trees and flowers. So, in the Dewey Decimal System, there can be slightly different numbers for flowers and trees: 582.13 Flowers 582.16 Trees Books about flowers and trees would be very close together on a library shelf, because their Dewey numbers both begin with “582.” But books about flowers would be right next to each other, followed by books about trees a little further down the shelf. In really large libraries that have many, many books about plants, the numbers could be even more specific: just for oak trees, or just for roses, for example.

19. IS THERE A PAGE ABOUT LIBRARIES IN THE GUINNESS BOOK OF WORLD RECORDS? "Next Time Someone Asks You Where the 300s Are" "Staff members at Northwestern University Library Cataloging Department have identified what is believed to be the longest Dewey number ever under serious consideration for assignment: a 23-digit monster for ARAB ATTITUDES TOWARD ISRAEL by Yehoshafat Harkabi, 301.1543012917492705694. The meaning of the number can be broken down as follows: 301-Sociology, 1543-Opinions, attitudes, beliefs on specific topics (Add 001-999); 301-Sociology; 29-Historical and geographical treatment (Add "areas"); 174-Region where specific racial, ethnic, national groups predominate (Add from Table 5); 927-Arabs and Maltese; 0-General relations between two countries (Add "areas"); 5694-Palestine, Israel. In other words: Historical and geographical treatment of opinions on countries where Arabs predominate, and their relations with Israel."

20. Sometimes it can be confusing to figure out how Dewey Decimal Numbers work on the library shelves. HINT: THINK MONEY!!!! AS IN DOLLARS AND CENTS!!! A high percentage of books have Dewey numbers that just extend to the hundredths place—two digits past the decimal point. This makes the numbers look a lot like prices, without the dollar sign! So, if you aren’t sure whether 919.65 is shelved before or after 919.57, THINK MONEY. Which is larger, $919.65, or $919.57? Remember that Dewey numbers get larger to your right and smaller to your left when you’re standing in the stacks (which is what librarians call shelving). So on the shelf, those two books will look like this: 919.65 919.57 ($919.65) ($919.57)

21. Here in the BMHS library media center, while we use the Dewey Decimal System to organize our books and other materials, we DO take a few liberties. For example, some libraries designate biographies (books about people’s lives) with 920; others with 921; others with B. Here we use 92 for biographies. Also, Mr. Dewey wasn’t really thinking about popular novels when he created his system. He placed Fiction in with Literature—the 800s. Most school and public libraries choose not to do this. Here at BMHS, we use F or FIC to designate Fiction.

22. In many school library media centers, there is another way the Dewey Decimal System gets “tweaked.” There can be many books on the same subject, like dinosaurs, or weather, or the American Revolution. All these books would have the same Dewey Decimal Number. And sometimes you don’t want just ANY book about dinosaurs, you want the ones by Don Lessem. So printed just below the Dewey number on the spine of the book (see Parts of a Book tutorial) there are three letters: the first three letters of the author’s last name. The combination of the Dewey Decimal Number plus the letters makes up the book’s “call number.” Fiction works the same way: on the spine you’ll see F or FIC on the top line, and the first three letters of the author’s last name below. A novel by Walter Dean Myers has the “call number” FIC MYE. Biographies are a little different. In BMHS, the Dewey Decimal Number is 92. The three letters below the 92 are the first three letters of the SUBJECT’s last name, not the author’s. So all the books about Eminem have the same call number: 92 EMI. And they’re right next to each other on the shelf. 567.9LES FICMYE 92EMI

23. The Dewey Decimal System is not the only way to organize libraries. But it is the one used most often in public and school libraries. College and university libraries often choose the Library of Congress system instead of Dewey. LC uses combinations of letters instead of numbers to designate subjects. Libraries that receive many documents from the government, like copies of Congressional bills, use a system called Superintendent of Documents. And collections of musical recordings may be organized by ANSCR, or the Alpha-Numeric for Classification of Recordings, which uses combinations of letters to stand for genres of music, like symphonies or opera or jazz.

24. Finally, always remember: IF YOU NEED HELP FINDING WHAT YOU’RE LOOKING FOR IN THE LIBRARY, ASK A LIBRARIAN!