PITARPA: CHAPTER 3

1. What is the difference between the Dewey Decimal Classification and Library of Congress system?

       The Dewey Decimal Classification (DDC, also called the Dewey Decimal System) is a proprietary system of library classification developed by Melvil Dewey in 1876.
       It has been greatly modified and expanded through 23 major revisions, the most recent in 2011.This system organizes books on library shelves in a specific and repeatable order that makes it easy to find any book and return it to its proper place. The system is used in 200,000 libraries in at least 135 countries.

       The DDC attempts to organize all knowledge into ten main classes. The ten main classes are each further subdivided into ten divisions, and each division into ten sections, giving ten main classes, 100 divisions and 1000 sections. DDC's advantage in using decimals for its categories allows it to be purely numerical, while the drawback is that the codes are much longer and more difficult to remember as compared to an alphanumeric system. Just as an alphanumeric system, it is infinitely hierarchical. It also uses some aspects of a faceted classification scheme, combining elements from different parts of the structure to construct a number representing the subject content (often combining two subject elements with linking numbers and geographical and temporal elements) and form of an item rather than drawing upon a list containing each class and its meaning.

               The Library of Congress Classification System (LC System) is used to organize books in many academic and university libraries throughout the United States and world.
The interdisciplinary nature of geography requires the use of material from a variety of subject areas. This outline, which is part of the Geography site at The Mining Company should assist you to locate areas of the library to begin your research.
               The LC System organizes material in libraries according to twenty-one branches of knowledge. The 21 categories (labeled A-Z except I,O,W,X and Y) are further divided by adding one or two additional letters and a set of numbers.