Universal Decimal Classification (UDC)

Universal Decimal Classification (UDC)

The Universal Decimal Classification (UDC) scheme of classification was developed in the year 1895 by the Belgium Barrister Paul Otlet and Nobel Prize winner Henri La Fountaine. The UDC is peculiar in the sense that it consists of a combination of both enumerative and faceted character of the schemes and hence it is designated as an Almost-Faceted Scheme of Classification. The UDC is derived from DDC as universal since it encompasses the whole field of knowledge. It is the multi-lingual general classification tool for organizing all kinds of recorded knowledge in the library. It is an international classification system mainly developed for the purpose of indexing and arranging an enormous card bibliography which not only includes books but also all kinds of documents, periodical articles, patents, trade catalogues, abstracts and other micro documents in more than 28 different international languages.UDC

The International Institute of Bibliography (IIB) was organized under the aegis of an International Conference on Bibliography held in Brussels in 1895. One of the main objectives was to devise a scheme of classification for its use in indexing world literature. The existing schemes of classification were found inadequate for the purpose therefore; it is an international extension and adaptation of the DDC, initially by two Belgians, Paul Otlet and Henry La Fontaine. The first edition appeared in French in 1905 as Manual du Repertoire Bibliographique Universel, which has 33,000 sub-divisions. The second edition was also published in French containing 70,000 sub-divisions. The third edition was published in German in 7 volumes of tables and 3 volumes of alphabetic index containing 140,000 sub-divisions. Full editions have also appeared in French, Spanish and Japanese languages. The publication of the English translation was started in 1943 entitled, “Universal Decimal Classification” and was designated as the fourth international edition. The British Standards Institution published the third revised edition of the abridged English Edition in 1961. The Abridg ededition of the UDC has been published in 13 different languages.

Purpose of UDC:

UDC is designed to serve the following purposes:

  1. To provide a method for arranging books on library shelves in an order which would be helpful to the users i.e. shelf arrangement.
  2. To provide a method of arranging sub-titles of the books themselves in a catalogue and printed bibliographies.
  3. To classify the recorded knowledge.
  4. To retrieve the document or locate the document.

Featuresof UDC:

UDC has following features:

  1. UDC is a practical scheme based on the demands of pamphlets, reports and periodical literature rather than the framework of a theory.
  2. The scheme is based on DDC and claims to be the first Analytico-synthetic classification scheme.
  3. It lays more stress to achieve co-extensive class numbers i.e. detailed specification than the achievement of a sequence of subjects for optimum helpfulness.
  4. It avoids the lacunae of numerous private classification schemes by providing astandard system covering all the disciplines and may be used in any type of library.
  5. It is a general classification scheme and not a bundle of special classification. It is rather an integrated whole.
  6. The scheme reflects exhaustive enumeration in the schedule with due provision for synthesis or coordination.
  7. It is amenable to adjustments to meet the special needs because acitation order in any given class allows alternative treatment.
  8. The use of synthetic devices like colon (:), permits coordination of concept in different permutation, there by minimizing the rigidity in the enumerated classification scheme.
  9. An International body for its maintenance and revision with full cooperation of its users guarantees the continual existence of the system as a current and up-to-date one.
  10. The terminology used in UDC helps in a comprehensive vocabulary of terms for indexing purposes.

Principles of UDC:

  1. It is a classification in the strict sense depending on the analysis of idea, content, so that the related concepts and groups of concepts are brought together and are arbitrary or haphazard systemization of alphabetical and other arrangements are avoided.
  2. It is a universal classification system for which an attempt has been made to include in it every field of knowledge not as a patch work of isolates, self-sufficient specialists grouping but as an integrated pattern and correlated subjects.
  3. It is constructed on the principals of proceeding from general to the more particular revision of the whole human knowledge into ten main branches each further sub-divided decimally to the required degree.
  4. It is a practical system for retrieval of information in which the order of subjects is not of much importance than the provision for detailed specifications.
  5. It also accepts the principles of mutually exclusive classes, collection of related subjects and consistency of approach.
  6. It has tried to remove national and racial basis to some extent by removing these factors and performing common facets.
  7. Its notation consists of Indo-Arabic numerals used decimally which allows infinite hospitality and social sciences.
  8. It employs certain notational techniques by which it is possible to link simple mainclass either which other main number with auxiliaries indicating place, time and similar commands used for categories.

UDC Notations and Symbols:

The UDC is based on the outline and the notational base of the Dewey Decimal Classification. The basic notation of UDC consists of Indo-Arabic numerals 0-9 used decimally, the different mathematical symbols and punctuation marks that have converted its notation into a mixed notation. The naught and decimal point have been omitted for convenience and have been implied. The numbers are simply indicated that is 0, 1, 2, 3, 4, 5—-. UDC uses single digit numbers and every digit is a significant one. However, the use of different signs and symbols has added qualities to the notation of UDC.

Symbols Expressed as Significance
+ Plus Connection of non consecutive numbers
/ Stoke Connection of consecutive numbers
: Colon Relation
[ ] Square Brakets Relation (Subordinate)
= Equals Language
(0) Brakets Naught Form
(0-9) Brakets Place
(=) Brakets Equals Race and Nationality
” “ Inverted Commas Time
A-Z A to Z Individual Sub-divisions
Hyphen Special Analytical numbers
.00 Point Double Zero Point of View
.0 Point Naught Special Analytical numbers

Structure of UDC:

The whole universe of knowledge in UDC is divided into two categories.

  1. Systematic Tables- The systematic tables are also called schedules which give the notational number of all basic class from 0-9. The general order and nomenclature of the main table is the same as DDC. The whole universe of knowledge is divided into ten main branches denoted by decimal fractions, Indo-Arabic numerals. UDC uses one-digit numbers for the main class. The main class numbers and their subdivisions are divided by a continuous extension of the decimal fraction on the principle of proceeding from general to specific. The practice of DDC to use a dot after every three digits has been retained in UDC. In UDC, the 4th class is kept vacant for future subjects.

Ten main Class of UDC:

0 Science and Knowledge. Organization. Computer Science. Information Science. Documentation. Librarianship. Institutions. Publications
1 Philosophy. Psychology
2 Religion. Theology
3 Social Sciences
4 Vacant
5 Mathematics. Natural Sciences
6 Applied Sciences. Medicine, Technology
7 The Arts. Entertainment. Sport
8 Linguistics. Literature
9 Geography. History

Revision Policy of UDC:

The Scheme is revised and updated from time to time by the International Federation for Information and Documentation (FID). The development and maintenance of UDC is achieved by FID at Hague through its ultimate coordinating body i.e. Central Classification Committee. This committee is assisted in its work, directly or indirectly by the National Committees, Special Subject Committees in each Country and International Subject Committees. Thus, it follows a decentralized procedure for revision of the UDC. The revision is done in the following three ways:

  1. Extension of topics by more detailed sub-divisions.
  2. Minor changes in the existing class numbers of sub-divisions.
  3. Starvation Policy introduced by Donker Duyvis. This policy assumes a fairly state of collection and opportunity for re-classification. Donker Duyvis used the unused notation in the dynamic and rapidly changing subject

If the users of the UDC want to suggest amendments or extensions to the schedules, they have to suggest the same to a National Body in their respective Countries. The changes in the UDC are communicated to its users by a half-yearly bulletin titles Extensions and Corrections to UDC. From the end of 1991 responsibility and updating was assumed by a new organization, the UDC Consortium (UDCC) who publishes the bulletin, Extensions and Corrections of the UDC.

References: (This document is collected from materials available from online/web and organize here for LIS students)

  1. RAJU (AA N). Universal decimal classification (IME-1993): Theory and practice: A self instructional manual. 2007. Ess Ess Publications; New Delhi. p-4- 9
  2. SARDANA (JL) and SEHGAL (RL). Universal decimal classification: Structure and methodology. 1983. Ess Ess Publication; New Delhi. p 1.
  3. KRISHAN KUMAR. Theory of classification. 1993. Vikas Publishing; New Delhi. p1.
  4. SHARMA (C D). Use of libraries: A guide to better use of libraries and their resources. 1978. Metropolitan Book; New Delhi. p-120.
  5. SHARMA (C D). Op. cit., p 121.
  6. KRISHAN KUMAR. Op. cit., p 4.
  7. INDIRA GANDHI NATIONAL OPEN UNIVERSITY (IGNOU). Unit 2: Needand purpose of library classification. IGNOU; New Delhi. p 26.
  8. DUTTA (Dwijendranath). Library classification: Theory and practice. 1962. The Western Book Depot; Nagpur. p 48.
  9. RAJU (Addepali Appala Narasimha). Dewey decimal classification (DDC 20): Theory and practice: A practical and self instructional manual. 1995. T.R. Publications; Madras. p 4.
  10. CHOWDHURY (G G). Introduction to modern information retrieval. Ed. 3. 2004. Facet Publishing; London. p 89.

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Md. Ashikuzzaman

Work at North South University Library, Bangladesh.

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