Take Our Dewey Challenge!
Ready to master Dewey Decimal? Ready to master information
science? Are you ready to find your way around virtually ANY
If you answered "YES", then you can
start our online quiz by clicking
HERE. Each question shows you a book and has 3 answer choices -
choose the one that correctly identifies which
general Dewey number the book belongs in. Good Luck!
Mr. B's Library Skills TV -
24/7 Online Video Lessons:
Do you have a lot of books? What if you
had many more? How would you keep track of them? How would you
find the book you want?
Libraries have many, many books. Librarians
need to know what books are in the library. A list of books in the
library is called a “catalog.” Today, libraries keep this catalog on
Librarians group books by what they are
about – the subject matter. This is how they are placed on
shelves. This is called “classification.”
Melvil Dewey, who lived from 1851 to
1931, invented a way to do this. His Dewey Decimal System is
still used today. Melville Louis Kossuth Dewey, the
youngest of five children, was born on December 10, 1851, in a
small town in northern New York.
Later he shortened his first name to
Melvil, dropped his middle names and, for a short time, even
spelled his last name as Dui. As a child, Dewey loved to
organize and sort things and also had a talent for mathematics.
Organizing a Library?
Before Melvil Dewey invented the Dewey
Decimal System, there was not a common way to organize
libraries. Books were very expensive then and much harder to
Most buildings were made of wood. There
were no fire codes. Fires were common. Think of all the things
in a library that would easily burn. Librarians were more
worried about fire than about how books were organized.
Libraries kept books in buckets so they
could easily carry them out if there was a fire. The most
expensive books were kept where they would be easy to grab and
rescue if there was a fire. This made it easy to save books if
the library was burning, but made it hard to find books to read.
To Dewey – this was not good. He loved
organizing and he loved math. He used these two ideas he loved
to create a system to keep books organized in the library. His
system is so good – we still use it today.
Thanks to Melvil Dewey’s Dewey Decimal
System, you can go in almost any public or school library and
use what you know from one library to find books in another.
Using Number Codes to Organize Books
What Melvil Dewey did was think about
what each book was about. He knew that when we look for books in
the library, we are interested in books by topic or subject.
Instead of organizing books based on the cost of the book, he
organized books based on what each book was about.
Books on the same subject or topic
should be placed together. This lets us easily find books on the
things we need or like to read about. In order to do this and
allow us to quickly and easily find books, Dewey created a
number code for each topic. The numbers use decimals – the
numbers have “dots” and then more numbers.
Think of all the different things we
could write or read about. We will need a lot of numbers. Dewey
created a set of 10 general subject areas – things that books
might be about.
These general numbers are in groups of 100. The decimals in the
Dewey Decimal System let us give each topic a special number or
General Dewey Numbers (by 100's)
To keep things simple, Dewey thought
about what people are interested in and how we share
information. He created a system of 10 main classes with 100
divisions and 1000 sections.
This means there THOUSANDS AND
THOUSANDS of Dewey numbers. Every topic you can imagine has its
own number! No one wants to memorize them all. You don’t have
To make things easier, we can look at
Dewey Numbers We will just look at the main classes or groups he
created. That will help you know what shelves to look at when
you want a nonfiction book.
100s – Who Am I? Books About Us.
The first section in Dewey are books that
are numbered from 100-199. The most important thing most people
are interested in is themselves. Some call this taking care of
#1. Dewey started by creating a group for books that are about
who we are. This means how we think and act. These are the
things that make us human.
200s – Who Made Me?
After we think about ourselves, many want to think about how we
got here. The next group that Dewey created is about religion
and Myths. These books try to explain how people got on earth
and why we are here.
300s – Who Is My Neighbor?
The next thing that interests people are the others around us.
Dewey knew there would need to be a groups of people to share
information with. These are books about how people live, the
things we do, and folklore.
400s – How Do I Communicate With
My Neighbors? If we have things
to share with our neighbors, we need to be able to talk to them.
This group of Dewey numbers is about languages, how we write,
500s – What Will I Talk About?
Now that we know our neighbor and how to communicate, we need
things to talk about. Dewey made this group for books about math
600s – What Will I Do With
After we learn about numbers and science, we need to find ways
to use it. The next Dewey grouping is about APPLIED SCIENCE. It
is about how we use science in medicine and technology.
700s – Time For a Break! What
Will I Do For FUN? We have
covered a lot of ground – almost everything we need to
understand ourselves, share with our neighbors, and use science.
Dewey knew that we would also want to relax and have fun. This
group is about arts and recreation.
800s – Time to Get Serious
Again: Authors and Books That Make Me Who I Am.
After a fun break, we look at the important books we read,
which we call literature. Famous authors and famous books are
important. They are so important that Dewey gave them a special
section in the Dewey Decimal System.
900’s – Who, What, Where, When,
Why? How Did Everything Happen?
In order to understand everything else, we need to answer these
questions. Dewey created a special section for geography and
Everything Else - Room to Grow!
Remember, Dewey lived a long time ago. He could never have
imagined many of the things we talk and read about today. He
knew this, so he created a special grouping for everything else
that would come along. This includes topics such as aliens and