Dewey Decimal Classification System

Dewey Decimal
Classification System
The Purdue University Libraries use the Dewey Decimal Classification System to classify and
arrange their collections. In this system, all knowledge is represented by 10 broad subject
classes:
000
100
200
300
400
500
600
700
800
900
Generalities
Philosophy and related disciplines
Religion
The social sciences
Language
Pure sciences
Technology (applied sciences)
The arts
Literature
General geography and history
The Dewey Decimal system is a hierarchical system, which means, within each broad class, it
develops progressively from the general to the specific.
For example:
600
640
646
646.7
646.72
646.724
646.7242
Technology (applied sciences)
Domestic arts and sciences
Sewing, clothing, personal grooming
Personal grooming
Personal appearance
Care of hair
Professional hairdressing for women and girls
Excerpts from Marty Bloomberg and Hans Weber, An Introduction To Classification and Number
Building In Dewey (Littleton, CO: Libraries Unlimited, Inc., 1976).
Each item in the Libraries has a unique call number and is filed under that number on the
shelves. To ensure that you find the exact item you want, be sure to copy the complete call
number.
10/90
How Call Numbers Work
Using decimal notation, books are
shelved numerically (left to right) by
the
h first
fi line
li in
i the
h call
ll number.
b
I
In
other words, they are arranged
number by number. For example
611.31 comes before 611.4 because it
is a smaller number.
All books of the same number group
are then arranged according to the
d line
li off the
h call
ll number,
b first
fi
second
alphabetically, then number by
number (D185n comes before D19a)
and then alphabetically again by the
last letter(s).
If all the information in the call
number is identical, the books are
h
arranged
d according
di
to
then
publication dates, chronologically
from oldest to newest. Multivolume sets are filed numerically
by volume number.