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Classifications Used at the U of I Library

A Brief History

 -- by Gail Hueting and Winnie Chan

The UIUC Library is the largest one in the U.S. that uses the Dewey Decimal Classification.  We still use it here for almost all print items (books and serials) going into the Main Stacks and most of the departmental libraries. Its adoption probably dates from the beginning of the 20th century.

DDC was conceived by Melvil Dewey in 1873 and first published in 1876.  It is based on a division of knowledge into ten classes:   000 generalities, 100 philosophy and psychology, 200 religion, 300 social sciences, 400 language, 500 natural sciences and mathematics, 600 technology, 700 the arts, 800 literature, and 900 history and geography. It is continually updated by an editorial policy committee.  The classifications for social sciences and technology have grown the most over the years.  The 22nd edition was published in 2003.

UIUC did not adopt all the successive editions of DDC.  It used the 14th edition for years and then adopted the 16th edition in the mid-sixties.  The Catalog Department Manual Part II, which is devoted to classification, states, "The 16th edition of the Dewey Decimal Classification, annotated with minor modifications, plus the special classification schemes given in the present manual, form the official classification at the University of Illinois Library."  At that time the exceptions were maps, the Law Library and the Oriental and Asian scripts in the Asian Library.  The S-collection in the Education Library used the Abridged Decimal Classification.

The largest exception to Dewey as published was and remains the 800s, Literature.  The reason is to keep works by the same author together and arrange them by broad chronological periods, as the LC Classification does.  The arrangements for German and Romance literatures go back to 1936.  (The letters A-O used under individual authors in the local scheme do come from Dewey and are listed under Shakespeare.)  In some other areas, UIUC stayed with earlier versions of the classification.   Mathematics, agriculture, and the World Wars were areas in which modified Dewey was used.

Most of these modified schedules, except for literature, were dropped with UIUC's adoption of the 18th edition in 1978.  At that time a general change to the Library of Congress Classification, which most other academic libraries were using by that time, was considered for a while.  However, it was felt that having a split collection would make it even harder for users to find the material they needed.  The Library has adopted every successive edition of Dewey since then because the Library of Congress supplies Dewey numbers on many catalog records.  We went to the 22nd edition last spring.

Not until Dewey 19 did the new Dewey was embraced with total acceptance.  The main issue was always keeping the stacks browse friendly.  Collocation of journals, conference proceedings, monographic editions, etc., was arguably the reason why the new Dewey number was rejected.

With the adoption of Dewey 20 and the suggested Dewey number by LC in 082 readily available, Dewey numbers taken from the newly adopted version have become a mandated practice for classifying new books, with copy in particular.  

There have been a few reclassification projects as a result of adopting new edition of Dewey.  While Dewy 22 contains no complete or extensive revisions, this was not true of previous editions.  In other words, in each new Dewey, many classes were revised or expanded either as a result of the development of the knowledge covered in the schedule as in the case of computer technology, or as a reflection of  social/technological developments of the time as in the case of the social, ethnic and gender studies areas.

The most complete acceptance of a new Dewey classification schedule at UIUC was the comprehensive reclassification project by the Mathematics Library in the 1980s.  The Math Library with the funding of a Title II grant, completed reclassified the library collection formerly classed within the 510-519 range, which were not even standard Dewey 16.  This involved remarking the books and shelflist cards not only in the Math Library but also elsewhere in the PSED as well as the Central Book stacks.

The Dewey website at OCLC says that currently:  "In the United States, 95 percent of all public and K-12 school libraries, 25 percent of college and university libraries and 20 percent of special libraries use the DDC. More than 200,000 libraries worldwide in 135 countries count on the DDC to keep their collections organized .."  Three of the largest Dewey academic libraries were located in Illinois:  Northwestern University, Southern Illinois University Carbondale, and UIUC.  The term is "were" because SIU Carbondale changed to LC in 2002.

You may not have known that the Library of Congress helps develop and maintain the DDC through its Decimal Classification Division.  The division adds Dewey numbers to more than 100,000 cataloging records each year.  The British Library assigns then too.  As a result we find suggested Dewey numbers for more than half of our copy cataloging.

Several UIUC departmental libraries changed to the Library of Congress Classification long ago.  For years the G, K and M schedules of the Library of Congress were so incomplete that the Map, Music and Law Libraries at UIUC were content to have their collections split with some DDC and some local schemes (for example, music scores and records collections, foreign laws collection, etc.).  Upon the completion of these three LC schedules, the Map, Music and Law Libraries adopted LC and gradually reclassified their Dewey collections into LC.  Law titles went unclassified for years before LC classification K began to be published.  The Music Library went completely to LC in 1989 when the 20th edition of Dewey came out after using it for scores for a long time before that.  It was adopted by the Asian Library for material in Asian languages in 1964. This unit, encouraged by the new language input application (CJK), also converted all of their small Dewey collection to LC in no time.


GPH 6/29/2007