Dewey Decimal Classification

The Dewey Decimal system coordinates materials on the same subject and on related subjects to make items easier to find on the shelves. The system uses a combination of letters and numbers.

How does the Dewey Decimal system work?

The basic thing to remember about the Dewey Decimal filing system is this: file digit by digit – not by whole number. For example:

•  451
•  451.01
•  451.012
•  451.023
•  451.04
•  451.04217
•  451.1
•  451.136
•  451.3

451.04217 comes before 451.1 because 0 is smaller than 1. Take it number by number and stop when two numbers are different. So in the example of 451.04217 and 451.1, you would stop at the 0. That is the first number in the sequence that is different, and 0 is smaller than 1 so it will be placed first. Look at our example list again. Does it make more sense now?

What is a call number?

Every book in the library is given a unique call number to serve as an address for locating the book on the shelf. The call number itself is composed of two parts – Dewey Decimal Classification and the Cutter number or book number.

Cutter Numbers
The cutter number for a book usually consists of the first letter of the author's last name and a series of numbers. This series of numbers comes from a table that is designed to help maintain an alphabetical arrangement of author’s names within a subject area. For example:

Beauchamp, Richard G.
Rottweilers for dummies
Boyd, Lee.
Canaan dog: a complete and reliable handbook
Brace, Andrew H.
Dog owner's guide to the boxer

What if the library has several works by the same author? How do we keep the call number unique? To do that a work mark or work letter is used to distinguish the various works of a single author. The work mark is a letter that is usually the first letter of the title of the book. For example:

Weiss, Rita
Knitting for the pampered baby
Weiss, Rita
24-hour crochet projects
Weiss, Rita
Little folks' quilts from big folks' patterns

If two Cutter numbers are identical, except one has an additional character at the end, it is shelved after the other: 371.914016 C43    is shelved before    371.914016 C43B

REMEMBER: the cutter number is read digit by digit.
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