UDC stands for Universal Decimal Classification

UDC stands for Universal Decimal Classification, which is a bibliographic and library classification system that represents the systematic arrangement of all branches of human knowledge

👉 . It was developed by the Belgian bibliographers Paul Otlet and Henri La Fontaine at the end of the 19th century. 

They created the Universal Bibliographic Repertory, which was intended to become a comprehensive classified index to all published information. They obtained permission from Melvil Dewey to translate his Dewey Decimal Classification into French, but they also made some innovations and modifications to adapt it to their needs

👉 The first complete international edition of the UDC was published in 1905 in French, under the title Manuel du Répertoire Bibliographique Universel 

👉 Since then, six more editions have been published, the latest one being the 7th edition in 2017.. The UDC has been translated into over 40 languages, including English, German, Spanish, Russian, Chinese, Arabic, and Hindi

 The UDC Summary, an abridged web version of the scheme, is available in over 50 languages.

Who is using UDC?

The scheme is in worldwide use, and has been published in whole or in part in over 40 different languages (see bibliography of UDC editions). It is used in bibliographic services, documentation centres and libraries in around 130 countries world-wide. Library collections indexed by UDC can be found in library OPACs and databases (see information about larger collections).

Who is managing UDC?

The International Federation for Information and Documentation (FID) managed the UDC, from its creation around the year 1900 until 1992, when it became clear that a more broadly based and financially autonomous organization was needed to administer and exploit UDC. 

FID, together with the publishers of the Dutch, English, French, Japanese and Spanish editions, became the founder members of a new body: the UDC Consortium (UDCC). The Consortium assumed ownership of UDC on 1 January 1992.

How is UDC maintained?

The UDCC appoints the UDC Editorial Team and the UDC Advisory Board with international membership to oversee the content of UDC and contribute to its revision.

The UDC divides the entire world of knowledge into 10 main classes, each represented by a digit from 0 to 9

👉 These are:

Main classes

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

Each main class can be further subdivided by adding decimal points and additional digits to create more specific subclasses.

👉 The UDC also allows for the construction of compound numbers to denote interrelated subjects or complex concepts by using various symbols and punctuation marks

👉 The UDC is an analytico-synthetic and faceted classification system that enables powerful content indexing and information retrieval in large collections

👉 It is widely used in libraries, national bibliographies, and databases around the world

Important common auxiliaries

=... Common auxiliaries of language. Table 1c

(0...) Common auxiliaries of form. Table 1d

(1/9) Common auxiliaries of place. Table 1e

(=...) Common auxiliaries of human ancestry, ethnic grouping and nationality. Table 1f

"..." Common auxiliaries of time. Table 1g helps to make minute division of time e.g.: "1993-1996"

-0... Common auxiliaries of general characteristics: Properties, Materials, Relations/Processes and Persons. Table 1k.

-02 Common auxiliaries of properties. Table 1k

-03 Common auxiliaries of materials. Table 1k

-04 Common auxiliaries of relations, processes and operations. Table 1k

-05 Common auxiliaries of persons and personal characteristics. Table 1k this table is repeated

Source : Wikipedia 

en.wikipedia.org. https://en.wikipedia.org/wiki/Universal_Decimal_Classification.