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What is the Dewey Decimal System?


Got a library book nearby? Pick it up and take a look at the label on the spine. What do all those numbers and letters mean?

You may have heard of the Dewey Decimal System. It’s a way of organizing books in libraries. Each book is given a unique number based on its subject: a call number. People use the call numbers to find books on the shelves. For example, let's look at this book, Schomburg: The Man Who Built A Library. Can you find the call number? Hint: look under "Copies and Availability."

An American librarian named Melvil Dewey invented the Dewey Decimal System in 1876. He was one of the founders of the American Library Association and made important contributions to the field of library science. However, he was also a racist. In 2019, the ALA voted to remove his name from one of their awards. But the Dewey Decimal System is still used in libraries all over the world. If you would like to learn more about how it works, the Kiddle Encyclopedia is a great starting point. Can you think of another way to organize books?

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