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Part 5: Searching for Information > Books


See also the outline of the Dewey numbers.

#1. Dewey numbers divide humanity's knowledge, ideas, 
and artistic creations into ten major categories 
spanning a range from 000 to 999:
000 Generalities

100 Philosophy & psychology

200 Religion

300 Social sciences

400 Language

500 Natural sciences & math arrow

600 Technology (Applied sciences)

700 The arts

800 Literature & rhetoric

900 Geography & history

#3. Each sub-category is further divided into nine specialized topics ranging from 1 to 9:

520 Astronomy

521 Celestial mechanics

522 Techniques, equipment, etc.

523 Specific celestial bodies arrow

524 [Unassigned]

525 Earth (Astronomical geography)

526 Mathematical geography

527 Celestial navigation

528 Ephemerides

529 Chronology

#2. Each major category divides into nine sub-categories spanning a range of 10 to 90. For example:

500 Natural science & mathematics

510 Mathematics

arrow 520 Astronomy & allied sciences

530 Physics

540 Chemistry & allied sciences

550 Earth sciences

560 Paleontology & paleozoology

570 Life sciences

 580 Botanical sciences

590 Zoological sciences

#4. By adding decimals, the specialized topics are broken down even further:

523.3 Moon

523.4 Planets

523.5 Meteors, solar wind, zodiacal light

523.6 Comets

523.7 Sun
523.71 Constants and dimensions
523..72 Physics of
523.73 Motions
523.74 Photosphere
523.75 Chromosphere and corona
523.76 Solar interior
523.78 Eclipses

Take a look at the complete breakdown of Dewey.

Thus the Dewey Decimal System is a hierarchical system, 
in which the arrangement of books on the shelves 
moves from the general to the specific.

Some of the Duke Libraries use other classification systems. For example, the School of Law Library, Fuqua Business School Library, and the Medical Center Library use the Library of Congress Classification System; Public Documents and Maps use the Superintendent of Documents (SU Docs) Classification System and other systems. If you need help using one of these classification systems, ask at that library's reference desk.


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Steve Cramer
Duke University Libraries
Guide to Library Research
Last Update: Tuesday, 27-Nov-2001 09:35:28 EST