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The Dewey Program at the Library of Congress

The Library of Congress > Acquisitions, Cataloging > Dewey > Frequently Asked Questions
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Questions

  1. Where do I find the Dewey number in the bibliographic record?
  2. Why do I see two segmentation marks in bibliographic records?
  3. How do I know if the Dewey number in the bibliographic record is current?
  4. If I see a problem with a Dewey number, whom do I contact?
  5. What is the difference between Library of Congress Classification and Dewey Decimal Classification?
  6. If I have a Library of Congress Classification Number, how can I find out what the Dewey number should be?
  7. Do you provide translations?
  8. What is the cooperative arrangement between the Library of Congress and OCLC?
  9. How do I subscribe to WebDewey?
  10. How can I access the Dewey training modules?

Answers

  1. Where do I find the Dewey number in the bibliographic record?
    The Dewey Decimal number is found in the MARC 082 field.

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  2. Why do I see two segmentation marks in bibliographic records?
    Prior to Edition 22, the rules called for a segmentation mark at the start of every standard subdivision (notation from Table 1) as well as at the end of the abridged number.   Old bibliographic records with Dewey numbers from previous editions are generally not updated to reflect current policies.

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  3. How do I know if the Dewey number in the bibliographic record is current?
    All bibliographic records should include the edition of the Dewey Decimal Classification that was used to classify the resource.  The edition is noted is in the MARC 082 field in subfield 2.  Edition 23 is the current edition.
    082 00 ‡a 940.3/2252 ‡2 23 (the number is from edition 23)
    082 00 ‡a 336.2001/9 ‡2 22 (the number is from edition 22)

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  4. If I see a problem with a Dewey number, whom do I contact?
    Please contact the Dewey Program at dewey@loc.gov with any questions about Dewey numbers in bibliographic records.

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  5. What is the difference between Library of Congress Classification and Dewey Decimal Classification?
    The Library of Congress Classification (LCC) system was developed at the turn of the 20th century and was specifically created to categorize books and other items held in the Library of Congress.   It features 21 subject categories with resources being identified by a combination of both letters and numbers.   For example, books on education are identified with a call number that begins with the letter “L” and those on political science under “J.”  The number of classes and numerous subclasses is not restricted.  Specific topics and geographic areas are often represented by alphabetic Cutter lists.  LCC notation does not lend itself to abridgment, except all the way to the summary level.

    The Dewey Decimal Classification (DDC) system was developed in 1876 as a means to organize all knowledge.   The DDC uses notation in Arabic numerals, well-defined categories, well-developed hierarchies, and a rich network of relationships among topics.  The ten basic classes are organized by disciplines or fields of study.   Each main class is further divided into ten divisions, and each division into ten sections.  Except for a few optional provisions, the DDC notation is strictly numeric. (See Alternate DDC notation for information about the optional alphabetic notation applied by the Library of Congress.)  In addition to summaries, the DDC has an abridged edition, with numbers that are the same as the numbers of the full edition, except shorter. (See Segmentation for information about segmentation marks that show the end of abridged numbers.)

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  6. If I have a Library of Congress Classification Number, how can I find out what the Dewey number should be?
    Classification Web is a subscription service which provides a number of correlation searching options, including LCC to DDC correlation functionality. There are very few one-to-one relationships between LCC and DDC, and they are scattered; most relationships are many-to-many. AutoDewey takes advantage of one of the few areas where LCC and DDC are similar enough to have clusters of one-to-one or one-to-few matches.

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  7. Do you provide translations?
    OCLC works with translation partners around the world in order to translate the DDC into a variety of languages.  Translation partners generally are based in and supported by national libraries or national library groups.  The translations are created, marketed (sold) and maintained by the translation partners in cooperation with OCLC.    Please contact dewey@oclc.org for more information.

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  8. What is the cooperative arrangement between the Library of Congress and OCLC?
    The Library of Congress and OCLC partner with each other under a formal cooperative agreement that OCLC will maintain an editorial office at the Library of Congress.

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  9. How do I subscribe to WebDewey?
    Please contact dewey@oclc.gov for information on how to subscribe to WebDewey.  Free trials are available on the OCLC Dewey web site.

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  10. How can I access the Dewey training modules?
    The Dewey training modules are available free of charge on the OCLC Dewey web site.   In addition, the Dewey blog is a great source for news and views on classification issues, as well as interesting and unusual DDC resources and curiosities.  It’s also a convenient way to share feedback directly to the DDC editors to help shape the future of the DDC.

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