How to read Dewey call numbers

1. Dewey Decimal System
Athens State University Library

2. Dewey Decimal Classification
The Dewey Decimal Classification uses numbers instead of letters in the beginning to
denote the classes of human knowledge:
• 000 – Computer science, information & general works
• 100 – Philosophy and psychology
• 200 – Religion
• 300 – Social sciences
• 400 – Language
• 500 – Science (including mathematics)
• 600 – Technology
• 700 – Arts and recreation
• 800 – Literature
• 900 – History, geography, and biography
The 10 classes are each divided
into 10 categories and each
division is again divided into 10
sub-divisions. This means that
the number created describes
an ever more specific subject.

3. Example of Dewey Classification
• Butterflies of the World / Valerio Sbordoni
Call # 595.789 S27b 1998

4. Explanation:
• Class 500 = Science (including Mathematics)
• Divided into 510, 520, 530…590 = Zoological Sciences
• Divided into 591,592…595= being other invertebrates [worms
and insects]
• Further divided with 595.7 = Insects
• Divided with 595.78 = Lepidoptera
• And that is divided into 595.789 = Butterflies
• So, if we use the ASU Library catalog and search for the book,
Butterflies of the World, …

5. Results for Search for the Title:
Butterflies of the World
• We find the book we
searched for, but
with the call #
595.789 S27b 1998.
• There is more to it
than merely 595.789.
Why?

6. Cutter Numbers explained
• The S27b 1998 is an
additional designation
needed because it is
possible to have two
books that have the same
beginning of 595.789.
1988
1998

7. Cutter Numbers cont.
• First letter of the author’s last name (in our example, the “S”)
• A series of numbers representing the rest of the author’s last
name. (the “27”)
• The first letter from the first “real” word in the title (the “b”)
• The 1998 is used for the publication date in case there is more
than one edition by the same author
• *Of course, there are exceptions to this rule in our collection, such
as the biography section.

8. Call numbers are arranged on the shelves by
INCREASING numerical value.
• 510 would be before 513
• 545.34 would be before 545.346
• 545.34 H22e would be before 545.34 H25w
• 545.34 H22e would be before 545.34 I22e
• 545.34 H22e 1988 would be before 545.34 H22e 1994

9. Shelving Sections at Athens State
• R= Reference
• F = Fiction
• J, JE, JR, JF = Juvenile
• z = literary criticism
• [RENTAL]
• [CURRIC] – Curriculum K-12
• [Big Book] or [Oversize]
• [*prof name* RESERVE]