Crash Course in
Dewey Decimal Classification
Fall 2014 iSkills Workshop Series
Instructor: Elisa Sze
Librarian, Collections & Public Services Coordinator
Faculty of Information, University of Toronto
Sept. 30 & Oct. 1, 2014
What is Dewey Decimal
Classification?
• Method of organizing knowledge, first by
discipline, then by subject
• Decimals allow the system to be
extensible
• Notation is based on Arabic numerals, for
universality
• Analytico-synthetic classification
Collocation: bringing together similar works
069 = about
museology/
museum science
069
A211
H972 = Cutter
notation for the
author’s name
069
H972
069
L653
Background
Date conceived
30+
languages
First published in
Who updates it now?
Library of
Congress
Current
copyright holder:
OCLC
135+
countries
Images:
DDC 1st ed. title page: https://archive.org/stream/classificationan00dewerich#page/n7/mode/2up
Portrait of Melvil Dewey: http://digitalgallery.nypl.org/nypldigital/id?1222486
World map: http://digitalgallery.nypl.org/nypldigital/id?464988
Formats & Editions
Print
DDC 23
Abridged 15
Online
WebDewey WebDewey 23
WebDewey  WebDewey
23  look for Abridged
Edition 15
The Abridged 15 is guided by the same
principles as the full DDC 23.
DDC 1 (1876)
000 Bibliography
100 Philosophy
200 Theology
300 Sociology
400 Philology
500 Natural Science
600 Useful Arts
700 Fine Arts
800 Literature
900 History
Source: Dewey, M. (1876). A classification and
subject index for cataloguing and arranging the
books and pamphlets of a library (Amherst,
Massachusetts: Forest Press Division, Lake Placid
Education Foundation). Page 12. Retrieved at:
http://quod.lib.umich.edu.myaccess.library.utoronto.
ca/m/moa/aey7382.0001.001/14?page=root;size=1
00;view=image
DDC 23 (2011)
000 Computer science, information & general
works
100 Philosophy & psychology
200 Religion
300 Social sciences
400 Language
500 Science
600 Technology
700 Arts & recreation
800 Literature
900 History & geography
Source: Dewey, M. (2011). Dewey decimal classification and relative index, 23rd edition. J. Mitchell
(Ed.). Dublin, OH: OCLC.
How to Classify
1. Determine the subject of the work.
2. Determine the DDC notation based on the
discipline of the subject.
3. Follow all instructions in the schedule and
relevant tables.
4. Keep in mind the rules of DDC.
Quick Warm-ups
http://dewey.org/webdewey/login/login.html
Diseases
Linguistics
Incunabula
Structural Hierarchy
Instructions and notes pertaining to one
number also apply to the numbers beneath it
in the same hierarchy.
700 The Arts contains a scope note
“Description, critical appraisal…”
The same scope note also applies to:
730 Sculpture
736 Carving
736.4 Wood carving
Notational Hierarchy
Each number is:
• Subordinate to the number that is 1 digit shorter
636.71 Breeds of dogs is subordinate to 636.7 Dogs
• Coordinate with numbers that have the same
number of significant digits
636.72 Nonsporting dogs is coordinate with 636.73
Working and herding dogs
• Superordinate to a number that is 1 digit longer
636.72 Nonsporting dogs is superordinate to 636.728
Poodles
Length of Numbers
• All numbers must be at least 3 digits long
• Some numbers will begin with 0 or 00
001 Knowledge
• No periods for 3-digit numbers
• Numbers longer than 3 digits have a
period inserted between the 3rd and 4th
digits
001.1 Intellectual life
Number Building
• Table 1. Standard Subdivisions can be
added to almost any number in the
schedule except when instructed
otherwise.
• Exceptions:
-
“Do not add”
“No number building”
Topics listed within “Including…” notes
When the topic is already covered by the
schedule (avoid redundancies!)
Number Building: 025 + T1
Apply the appropriate standard subdivision
to the base number 025.
Standard
Subdivision
Dictionary of
library operations
Journal of library
operations
A museum of the
artifacts of library
operations
Final Notation
Number Building
• Tables 2 to 6 can only be added when
specifically told to add them.
• Other instructions for number building
appear in the schedule, when applicable.
Number Building: Notation for
ROM using 069 + T1 –09 + T2
069.09 Historical, geographic, or
biographical treatment of Museology
See instructions for:
T1 –093 - T1 –099
Look out for…
• Discontinued
numbers [ ]
• Optional numbers ( )
• Tables of preference
at the beginning of T1
and throughout the
schedule
• Footnotes *
• Center notes >
• Notes
–
–
–
–
–
–
–
–
–
Add
Build
Class elsewhere
Class here
Comprehensive works
Do not use
Including
See Manual
Scope notes
Rules for More Complex
Classification
Rules of DDC
Rule of application
If a work deals with
interrelated subjects in
the same discipline,
class the work with the
subject that is being
acted upon.
Example
Administration 101 for
museum professionals
“Actor”: Administration
Subject that is “acted
upon”: Museums
Rules of DDC
Fuller treatment
If a work deals with
two or more subjects
in the same discipline,
class the work with the
subject receiving the
fuller treatment.
Example
A book that is mostly
about photography, with
a bit about painting
Subject receiving fuller
treatment: Photography
Rules of DDC
First-of-two rule
For two subjects
treated equally, class
the work with the
subject whose number
comes first in the DDC
schedules.
Example
A book that is 50% about
photography, 50% about
painting
Subject whose number
comes first: Painting
Rules of DDC
Rule of three
If a work covers
equally 3 or more
subjects that are all
subdivisions of a
broader subject, class
the work in the first
higher number that
includes all the
subjects.
Example
A book that is equally
about mathematics,
astronomy, and physics
First higher number that
includes all the subjects:
Science
Rules of DDC
Rule of zero
Keep only as many
zeroes as necessary
for distinguishing a
standard subdivision
from the regular
numbers in the
schedule.
Example
700
The arts (fine,
decorative, literary,
performing, and
recreational)
700.1 Philosophy of art
701
Philosophy of fine
and decorative arts
720
Architecture
720.1 Philosophy of
architecture
Rules of DDC
Interdisciplinary
numbers
If the work treats the
subject from multiple
disciplines, and an
interdisciplinary number
is provided in the
schedules or Relative
Index, use the
interdisciplinary number
when applicable.
Example
001.9
Controversial
knowledge
“Class here interdisciplinary
works on controversial
knowledge, parapsychology,
occultism.”
Rules of DDC
• Table of Last Resort
• Intention of the author
Your Turn
• Work in pairs or groups of 3.
• Determine the notation for each topic.
• For topics where more than 1 notation
is possible, explain your choice of
notation.
• For notations that you build, explain
the instructions that you used.
Freedom of information
Semantic Web
A museum collection of
historical ball gowns
Artistic depictions of the
natural sciences
For additional practice with
DDC, try the exercises in
your handout.
Evaluations
http://current.ischool.utoronto.ca/
classificationwithdewey/fall2014