| Offical Name | Universal Decimal Classification |
| Description | The Universal Decimal Classification (UDC) is a document indexing language in the form of a classification scheme covering the whole universe of knowledge.
The UDC is designed for subject description and indexing of content of information resources irrespective of the carrier, form, format or language |
| Last Release |
UDC MRF12 (December 2018) |
| Next Release |
UDC MRF13 (planned release 2023) |
| Updates/Frequency | Annual: a new version of the scheme is released annually, containing extensions and corrections |
| Size |
72,000 subdivisions |
| Languages |
57 languages (varying extent of detail) |
| International Use |
135 countries, 150,000-250,000 document collections worldwide |
| Application Areas | Libraries, bibliographic databases, bibliographies, documentation services, information portals, online databases, publishing (e.g. journal articles) |
| Type of Classification |
Analytico-synthetic & faceted classification |
| Subject Coverage | All areas of knowledge (disciplines, subdisciplines, subjects). See Subject coverage statistics |
| Knowledge Presentation | Based on disciplines (subdivided hierarchically) with synthetic features; the UDC schedules are organized as a coherent system of knowledge with
associative relationships and references between concepts and related fields |
| Vocabulary Organization | Classes are organized in the tables of common concepts (context-free concepts) and in tables of main knowledge subdivisions subject classes |
| Type of Notation | Numerals (decimal), symbols and letters of the alphabet as alphabetical extensions. Notation is hierarchically and syntactically expressive: the longer the
number, the deeper the hierarchy, components in complex expressions are indicated by symbols and punctuation |
| Ownership of Copyright | UDC Consortium, The Hague |
| Maintenance | UDC Consortium: UDC Editorial Team |
| Distribution | UDC Consortium and licensed publishers |
| Contact | mail@udcc.org; http://www.udcc.org |
| Associated Publications | Extensions & Corrections to the UDC (ISSN: 0014-5424) |
| Copyright Restriction | UDC use in document indexing is free and unlimited in any context (libraries, bibliographic services, Internet, commercial-non commercial).
The distribution and publishing of UDC content in the form of schedules whether in their entirety or as a subset are restricted to holders of a publishing licence |
| Online Schedules | |
| free access: | Multilingual UDC Summary |
| UDC linked data |
| Croatian: Hrvatski UDK Online |
| Czech: České MDT Online |
| Polish: Polska UKD Online |
| Serbian: Српски УДК Онлајн |
| Slovakian: Slovenské MDT Online |
| paid subscription: |
English: UDC Online English |
| Dutch: UDC Online Nederlands |
| French: CDU Online Français |
| Spanish: CDU Online en Español |
| French: CDU Online Français |
| Slovenian: Univerzalna Decimalna Klasifikacija - UDCMRF12 |
| Data Format | Maintained in database (mySQL, standard release is in English language distributed as a file to publishers and users,
tagged text exports, XML exports. |
