A man named Melvil Dewey developed the Dewey Decimal Classification System in 1876. He thought that it would help libraries organize their books better if each book was given a number according to what it was about. That way, all books with the same subject would be close to each other on the shelf. That's what "classification" means.

The word "decimal" refers to numbers that are based on 10 (ten). You will see that there are 10 basic categories in the Dewey Decimal system, and each of those categories is further split into 10 categories, and so on. The number 10 has always been a good number for people to use in counting things because we have 10 fingers!

Each one of the 10 major categories in the Dewey Decimal system covers a different subject. For example, the 300 category includes everything about the Social Sciences, like Government or Law. The 800 category includes everything about Literature. Once you get used to how things are organized, you'll find it very easy to locate the information you're looking for.

Melvil Dewey thought up this system just for organizing books, because there wasn't much else in libraries back in 1876. However, the Dewey Decimal system is also very good for organizing other kinds of information, like websites. Today, many libraries still use the Dewey Decimal system, even though they might have things like videotapes, compact discs (CDs), and computer files as well as books in their collections.

You may notice that the Dewey Decimal system pays more attention to American and European subjects than to those of other cultures. Back in 1876, many people didn't understand the importance of a global perspective and learning about other cultures. The Dewey system still reflects that old outlook because it would be very hard for libraries to completely change how they are organized. Someday, though, we hope that the Dewey Decimal system will more fairly represent the diversity of our world.

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