17 Introduction to major classification systems: structure and features of UDC
Dr M P Satija
1. Introduction
The Universal Decimal Classification (UDC) is known by many names such asEuropean Dewey, Brussels Classification, and the International decimal classification. Being based on the Dewey’s System, it was called Expanded Dewey in the beginning. Nevertheless, it is the first truly International classification designed by an organization and also the first one meant for bibliographic and documentation work — all earlier systems were for shelf arrangement designed by individuals. It continued its development as a retrieval tool. Nevertheless, it is equally efficient as a library classification and tool for organizing other entities and objects. It has become a highly flexible and effective system for organizing bibliographic records for all kinds of information in any medium. For multimedia packages it is highly suitable. Electronic UDC is now seen as a retrieval tool of the future.
It is a multilingual and general classification for all fields of knowledge. All branches of knowledge have a place in UDC, through traditionally it is considered more strong in science and technology subjects.
2. Brief History
In 1895 some system of classification was required by the then newly established International Institute of Bibliography (IIB), which later changed name to International Institute for Documentation (IID). 1914-1937), and later became International Federation of Information and Documentation (1958-1985), and International Federation of Information and Documentation, 1986-2001). FID (with its office in the Hague) was closed down in 2001 due to financial failures. Task of the IIB was to compile a universal bibliography, a Repertoire bibliographique universal. It needed a system for arrangement of entries in this universal bibliography – a systematic list of technical literature published anywhere in any subject and language since antiquity. This bibliography could only be in a classified order to transcend the language barrier. By 1921 the IIB had collected 12 million references on cards. Two Belgians Paul Otlet (1869-1944) and Nobel laureate Hernri La Fontaine (1854-1943), founders of the IIB, discovered the DDC and sought permission from Melvil Dewey (1851-1931) to use and expand DDC for arranging items in the bibliography. After obtaining necessary permission they brought out expanded and powerful classification equipped with more details and added synthetic equipment for class number synthesis for micro documents. To the DDC they added dimensions, depth and flexibility. It is credited as the first facetedclassification, a harbinger of the Colon Classification in 1933, though SR Ranganathan claimed his classification was invented independent of the UDC. In course of history it has proved an apt classification for information analysis and retrieval, and a classification for highly specific subjects encountered in documentation work.
First edition based on the 5th edition of DDC (1894) appeared in French between 1905-1907 under the title Manual du Reperoire Universals. It consisted of 33,000 classes. The 2ndedition again in French was published between 1923-1933, and was titled Classification Decimal Universalle. The third German and fourth English editions werebegun in 1933 and 1936 respectively. Development of the UDC has been divided into the following three historical periods by Rayward:
1. French Period, 1895-1933: Foundation and grammar
2. German Period, 1933-1952 Details and expansion
3. English Period, 1936-1975 Research and practice
To this we can add:
4. International Period, 1990 Technical and strong organizational improvement
The completed English edition published in numerous small fascicules took half a century– due to alleged neglect.
3. Various Editions
Throughout its history, it has been made available in editions of varied details. Till 1990, there were Full, Medium and Abridged editions. Full edition consisted of about 200, 000 terms, Medium had only 70,000 terms, about 30% of the Full, and Abridged had 22000 terms, about 10% of the Full edition. At present these versions are no longer officialor exist. Now only standard version of 66, 000 terms, and the Abridged of 4100 classes are the official editions. In addition to the earlier available different full, medium and abridged editions, in 1999 was published the Pocket edition in English, and other languages. There is a plan to revive the pocket edition.
A core version of the UDC having 70, 000 subdivisions is now available in a database format. It is called the Master Reference File (MRF), which earlier was in all the three official languages namely, French, Garman and English. But now it is mostly inEnglish. A UDC Summary of about 400 classes is available on their website, which soon is being upgraded to 1000 classes.
3.1 Current Edition:
Now due to organizational changes the following two edition are available: Standard edition of about 66,000 entries is available in print and electronic database in CDS/ISIS. ISO 2709 compliant MRF data designed in UNESO’s CDS/ISIS contains the UDC tables with other records required for administration, maintenance and archival. It is a comprehensive tool with the UDC consortium is and is also made available tothe license holders. To support its multiple functions in fact there are three MRFs. It is the UMRF(user MRF) version which is available for distribution to the public(www. udcc.org/mrf.htm).
Derived from the MRF the print edition in two volumes has the following bibliographic details:
Universal Decimal Classification, complete edition, London: BSI, 2005, 2v.–vol. 1. Systematic tables (ISBN 0-580-45469-X)–v.2 Alphabetical index (ISBN 0-580-45470-3).
It may be mentioned that the BSI is no longer a member of the UDCC and consequently its publisher UDC online is the complete first edition available electronically. It has many additionalfeatures over the print version which allows multiple searching by terms and numbers. Online version multi-usersfacility on user friendly screen and also provides number building facility. Cut paste facility saves time and effort. NowUDC MRF files have been moved to a new database with extended functionality. It willprovide more diversified and improved products. Standard online edition cannot bepurchased. Multi-user license to use it usually on a LAN can be obtained from the UDCC office in the Hague, the Netherlands. A guide to the application of the MRFcalled the MRF Manual, is available free of charge to all Consortium members and license holders.
The English version of the abridged edition was available on order from the British Standards Institution (BSI), London(www.bsi.org). A new and revised edition is expected in 2014. UDC online allows free access on trial basis or for teaching for two weeks.
4. Main Features
1. UDC is a practical bibliographic classification: truly international in efforts and exposition of contents. Considered as the first faceted classification, it is a synthetic classification which is able to specify minute subjects, aspects, formats and their varied viewpoints.
2.It is the first officially multilingual classification being published in French, German and English.
3. 2.1 Its 1000 sections summary is available in about 50 languages
4. Its notation is independent of any particular language or script, and its translations have appeared in about 50 languages.
5. It lays more emphasis on subject analysis and document specification.
6. Auxiliary apparatus of relations and synthesis is quite powerful. It makes the UDC a truly
multidimensional scheme.
7. It is thus more suitable for micro documents, electronic information and information retrieval in online and networked databases, and websites.
8. Its structure is flexible to accommodate new subjects, and change citation order for flexibility of shelf arrangement and searching.
9. It has A-class machinery for governance, maintenance and marketing. It is called UDC Consortium which has a full time director, a full time editor, and an international advisory board.
5. Organization of Knowledge and Layout of the Schedules (Main Tables)
It is a general classification covering the whole domain of knowledge. As already said, it has borrowed its basic structure from its parent the DDC, with the exception of merging main classes 4 with 8 Literature. The main class 4 is still vacant. The main classes thus are:
0 Generalities
1 Philosophy. Psychology
2 Religion. Theology
3 Social Sciences
4 [Vacant]
5 Natural Sciences, Mathematics
6 Technology
7 The arts
8 Language. Linguistics. Literature
9 Geography. Biography. History
Unlike the DDC there is no condition of minimum of three digits in a class number.
Each of the main class has been further divided into 10 divisions:
5 Natural Sciences
51 Mathematics
52 Astronomy
—
—
59 Zoology
There are thus 10 x 10 =100 divisions including the vacant places. Similarly the above 100 divisions can be divided again into 1000 sections:
53 Physics (General)
531/534Mechanics
| 535 | Optics |
| 536 | Heat & thermodynamics |
| 537 | Electricity & Magnetism |
| 538 | Physical nature and matter: (Atomic & Nuclear Physics) |
| Each of the above classes can be further divided decimally. | |
| 536 | Heat and thermodynamics |
| 536.2 | Heat Conduction |
| 536.5 | Temperature |
| 536.6 | Calorimetry |
| 536.7 | Entropy |
A dot has been put after the third digit. In fact a dot is put after every third digit of thesame facet, e.g. 621. 882 Bolts, Screws…
621.882.215 Round-headed screws…
621.882.215.3 Round-headed screws and bolts with cross recesses
The schedules 0/9 and its subdivisions are known as Main Tables.
6. Auxiliary Tables
Any number from the main table can be extended by notation from auxiliary
A) Common Auxiliaries: Universally applicable to all classes for subject and document specification.
B) Special Auxiliaries: Applicable restrictively to a specified class.
6.1 Common Auxiliaries
More than 10,000 Common Auxiliaries are given in Tables la to lk:
Two or more auxiliaries can be added simultaneously:
Foreign relations between Pakistan and India: An Urdu text
327 (540: 549) =214.22
Hindi-Urdu journal of Indian foreign policy
327(540) (05)=214.21=214.22
Birds of India and Nepal: A textbook in Bengali
598.2 (540+541.35) (075) =214.32
Weather on 1st January 2014 in India: a report
551.5 “2014.01.01” (540) (047)
Critical study of the Tragic Plays of William Shakespeare
821.111 Shak-21.09
Psychology of single parents
159.9 – 055.52 –058.832
6.2 Special Auxiliaries
These three kinds of auxiliaries are applied to a restricted but clearly specified range of numbers. Their functions overlap. These are recognized by sidelining the numbers. These are denotedby
.0 point naught
‗ Apostrophe
-Hyphen,
53Physics
53.02General laws of phenomena
53.081Units and constants [Physics]
It means that the special auxiliaries .02 and .081 shown by sidelining 53 are applicable toall the subdivisions of 53 Physics, e.g.,
| 531.02 | General Laws of mechanics |
| 531.5.02 | General Laws of gravity |
| 531.55.02 | General Laws of external ballistics |
| 531.55.081 | Units in external ballistics |
| 534.6.081 | Units of acoustic measurement |
Hyphen auxiliaries:
546 Inorganic chemistry
546-31 Oxides
546.26 Carbon element
546.26-31 Carbon Oxides
546.47 Zinc
646.47-31 Zinc Oxides
6.3 Citation Order
As clear from the above examples two or more auxiliaries can be added to a given class number.The UDC follows the Principle of Inversion: that is, the order of facets in the class number is reverse of their arrangement on the shelves. Broader citationorder is: Class number +Special auxiliaries + Common auxiliaries. The common auxiliaries are to be added in the order of their decreasing specificity – i.e. more important or specific common auxiliaries is to be added first and the least specific to be added last. A mechanical formula for the citation order is that, the auxiliary tables should be added in the order 1k to 1c.
Unemployed Medical librarianship graduates in India in 2000 CE : A motion picture in Hindi
026: 61-577.19 (540) ―2000‖ (084.122)=214.21
However, no formulated order has been presented for the special auxiliaries.
The UDC being a flexible classification the order may be changed to have better sense or make some local variations Moreover to arrange documents the shelled auxiliaries may be brought in the fore position. For example, to bring all journals in one section we could have numbers like:
7. Notation and Layout:
The UDC notation is a mix of decimal numbers, mathematical and punctuation signs with permissible use of alphabets, arithmetic numbers, or other non-UDC symbols. The use of decimal notation has made it a truly international classification with many technical advantages. It is hierarchical, expressive, hospitable, mnemonic, faceted and synthetic. Instead of verbal signs, some symbols independent of language have been used to give notes and instructions under an entry in the schedules:
| Symbol | Name | Meaning |
| Arrow | See Also | |
| à | Diamond | Examples of built numbers |
| Square | Inclusion note | |
| | | Sideline | Special auxiliaries |
| * | Asterisk | Non-UDC numbers |
| A/Z | Alphabets | Alphabetical divisions |
The symbols are only to interpret the tables correctly, and never make a part of the class number.
These tables, both main and auxiliary, consist of simple numbers and a few compound numbers –latter are a compilation of two or more numbers built with linkage sign orauxiliaries. Such numbers are indicated by àsign, e.g.,
| 56 | Paleontology |
| à56:581 | General Paleontology |
| 030 | General reference works Encyclopedia |
8 Index
Terminology is current which uses British spellings and idiom. In the index of the abridged edition there are 9500 main and 3500 subentries making a total of 13000 contained in 107 pages. It gives an average of three access points per entry in the tables. Index entries culled from the electronic files are arranged in word-by-word order to conform to the BS ISO 999 Standard. Specific names are entered following AACR2 specifications. It includes all the principal divisions, inclusion notes, common and special auxiliaries and built-in compound numbers. Collocation of terms depicts relations and qualifiers are added to homonymous words to show the context, e.g., axes (tools), 672.7;axes(plants), 581.4, or line(art), 7.013. In case of a synonym all its popular terms are indexed to avoid see-references, e.g., both Aves and Birds have been indexed.
Index is tidy and easy to use.
9. Management, Maintenance and Revision
Since the 1990s the UDC has undergone a sea change in its technicalities, contents organizations and management. It has been completely rejuvenated. The original FID/CCC, the committee in charge of the UDC, was replaced in 1985 by the UDC Management Board. On the recommendation of a Task Force constituted by the Board, the FID(now defunct) handed over the ownership of the UDC to the non-profit, but self-financed UDC Consortium which came into being on I” January 1992. Since 2007 it consists of thepublishers of the Dutch, English, French, Russian, Spanish and Czech editions of the UDC (www.udcc.org). The UDCC owns, markets, maintains innovates and keeps the UDC updated.
The office of the UDCC is housed in the National Library of the Netherlands at the Hague and is a managed by a full time director, now Alan Hopkinson. The UDCC also appoints editorial team and the Advisory Board The first full time editor of the UDC was Professor Ms Ia. C. McIlwaine (1993-2006) who was succeeded by Maria Ines Corderio. Since May 2010the current Editor- in- Chief is Dr. Aida Slavic. Chief editor is helped by 12 member UDC Editorial team. Each of the consortium members has the right to issue UDC edition in its own language. Language versions are not mere translations. These are updated with local and cultural additions. The UDC Advisory Board consists of about 20+ information professionalsfrom all over the world.
A UDC discussion list moderated by Dr Aida Slavic exists at UDC-FORUM@ JISCMAIL.AC.UK. <wwiv.jiscmail.ac.uk/listsiudc-forum.html>.It is a forum to get and share UDC news and developments. UDC blog exists at http://universaldecimalclassification.blolc,spot.com
9.1 Revision
The UDC revision though slow is well planned and extremely regular. The UDCC controls its development acting as an international clearing house. It seeks help from specialists in many subject fields. Editorial revision is quite democratic and broad based. Revision proposals are circulated among consortium members, advisors and users for comments before finally incorporating in the MRF. With the appointment of full time Editor for the first time since September 1993, the pace of revision has become quick. Users are informed of changes and expansions in the annual publication: UDC: Extensions & Correctionspublished every year in November(Vol.35: 2013). This annual also contains articles, major revision proposals and a bibliography on the UDC. Editions of the UDC incorporating the authorized changes are published by the members of the consortium, each in its own language, or by any outside publisher licensed by the UDCC.
9.2 Problems
Despite its constant and enduring success, it has been criticized on certain points:
1. Its DDC base has always been criticized. It has mortgaged its future to the DDC, it is often said, ruefully.
2. Some notational devices, although apparently logical and satisfactory, cause problems in retrieval systems.
3. Symbols like — and 0 overlap in function and may lead to confusion.
4. Its auxiliaries are still developing with changes in some notational symbols.
5. There are certain citation order problems, as no definite standard has been prescribed.
6. Main class 4 has still not been filled up.
7. Frequent notational changes are worrisome.
8. Lacking support/sponsorship of any institution it is financially not sound
10. Use
In terms of its applications, now it is a most diversely used tool ranging from shelf classification, organizing bibliographies, web organization to classification of conceptual and material objects. Though the first bibliographic classification, it is equally useful for arranging documents, their surrogates and other information bearing objects such as electronic files, AVs, maps, CDs , art collections, photographs, coins, stamps and entities like persons, places and organizations.
Today, UDC is ranked as one of the big three classification systems of the world. Technically, it is considered much superior to the other two, namely the DDC and the Library of Congress Classification. It is used in about 100, 000 libraries and information centers in 130 countries especially in Europe and Latin America. Its use was mandatory in the S & T libraries of the erstwhile USSR. Translated in 40 languages and 5 scripts, it is also usedin about 20 national, subject and trade bibliographies including theWalford Guide. The abridged edition is equally useful for teaching.
It has been a pioneer in finding its use in computerized databases. It works extremely well with computers. Its hierarchical structure and classified order is useful forcomputer screen browsing and searching. Its hierarchical and synthetic notation is helpful in accurate retrieval. Online UDC allows multiple search facilities, namely, string search in natural language,Boolean searches, and browsing up and down the hierarchy. It pioneer use in OPACs has been successful. It is already being used on several subject gateways and websites to arrange directories of references, e.g., (UK) National Information Services and System (NISS) Directory of Networked Resources (www.niss.ac.uk). In subject gateways,)can be put to the following uses: Manual Classification of manual collection; manual classification of large number of automatically harvested resources by using metadata; and, automatic harvesting and classification (Slavic, 2006).
It has emerged as an excellent source for building other indexing languages, thesauri, taxonomies and special classifications with its multilingual database. It has the potential to act as a switching language between different information systems.
Its use outside the library is increasing. The UDC has emerged as knowledge organization tool of high quality, easy applicability and international validity.
10.1 Future
As said earlier, UDC has been criticized for its DDC core and slow development. It has also been remarked that the UDC had better not been invented, yet it has not only survived but thrived in the bibliographic world where mortality rate is high. Once introduced, it not only works but performs better than many of its competitors.
For a century, despite lack of adequate finance and manpower it has kept its head above waters. It has rejuvenated itself with constant reorganization since the last two decades. It is coping with updating by restructuring the knowledge using the framework of the Bibliographic classification (BC-2) – latter is much more up-to-date and better structured than any the other general scheme. Class 61 Medicine has been used as a pilot project by Ia. C McIlwaineand Nancy Williamson to change it to a fully faceted structure.
During an IFLA, etc sponsored international seminar on UDC in June 2007(www.ulec.org/seminar2007.htm) at UDCC headquarter, a Dutch software company Magnaview(www.magnaview.nl) presented an innovative visual application of the UDC. It makes possible to view the UDC MRF in twenty novel ways and interact it with visually. The software is commercially available from the company for the MRF licenseholders.
With its well organized promotional network and keenness for innovations the UDC seems surely to havean assured long future
11.Key words
1. Abridged Edition concise version of the UDC having about 2000 classes meant small libraries. It is also considered as an excellent tool for teaching UDC.
2. Auxiliary tables
Somenon-core tables of general concepts to specify subjects and documents. There are two types of auxiliaries : Common Auxiliaries in tables 1a to 1k; and Special Auxiliaries which provide further details of subjects all applicable to narrower areas of subjects. Different classes have different special auxiliaries only applicable to them.
3. Full Edition
Erstwhile the largest edition of UDC containing more than 2 lac classes. Since 1990s it has been converted into standard edition which now contains about 70, 000 terms and is considered sufficient for libraries. Librarians requiring more details can still resort to the former full edition available in fasicules only.
4. Main tables
The schedules of the UDC having details of the 0/9 classes. It is the core of the UDC. The other tables are called auxiliary tables
5. Master Reference File (MRF)
The MRF is definite, authorized most update and comprehensive database of the UDC main and auxiliary tables along with other needed records for administration, maintenance and archiving. It is maintained as the working tool for the editors and UDCC to revise, translate derive and distribute various editions, versions and products d for marketing and research. It is accessible only to the licensed users. For reasons of efficiency the size of the MRF is kept to about 70, 000 representative terms. In fact there are three MRFs. The language of the MRF is English but has the capability to hold description of UDC number in many other languages.
6. UDC Consortium
Established in January 1992 it is a non-profit but self-financed organization of UDC publishers. Managed by a full time director UDCC is housed in the Royal (National) library of the Netherlands at The Hague. It owns, maintains, innovates and markets the UDC and its products. It is also charged with the administration of the UDC as it also appoints the UDC editorial team and the UDC advisory board
7. Universal Bibliography
An ideal bibliography of all subjects in all languages published anywhere at any point of time. Such a bibliography is a utopian dream. Many have dreamt of such a project but could never execute it due to too obvious reasons. Founders of IIB (1895) gave up this project even after collecting 12 million references. Bibliotheca universalis (4 vol., 1545–49), an index in Greek, Latin, and Hebrew of writings in all languages compiled by Swiss naturalist Konard von Gesner (1516-1565) is considered to be a universal bibliography of its time.
12.Reference& Notes
- Satija, M P . ―Pocket edition of the Universal Decimal Classification‖Lib. Herald 38(1) 2000: 1-7Robinson, G. ―Abridged UDC” Knowledge Organization 26(3) 1999: 149-156
- British Standards Institution.Universal Decimal Classification, Pocket edition/ DISCPD 1000: 1999; 288p. ISBN 0-580-33045-1 www.bsi.org.uk/discwww.udc.org
- Universal Decimal Classification, Abridged ed. London: The BSI, 2003, 266p. ISBN 0-580-42440-5.
- http:// www.ude-online.com
- McIlwaine, Ia. C. ―UDC Centenary: the present state and future prospects‖Knowledge Organization 22(2) 1995: 64-69
- McIllwaine, Ia.C. The Universal Decimal Classification: A guide to its use.The Hague: UDCC, 2007, 278p. ISBN 978-90-806152-3-6.Reyward, W. Boyd.―The UDC and FID: A historical perspective‖The Lib Quarterly 37(3) July 1967: 259-278.
- Slavic, Aida ―UDC in subject gateways: experiment or opportunity‖Knowledge Organization 33(2) 2006. 67-85.
- Slavic, Aida; Corderio, Maria E and Riesthusi, Gerhard. ―Maintenance of the Universal Decimal Classification: Overview of the past and preparation for the future‖. To be published in 2008, available on www.udcc.org
- Select literature on the UDC is available on dList the Digital library of Information & Technology dist. sir. arizina. eddies.
- www.udc.ora/index.htm
- http:///universaldecimalclass1fieation.bloaspot.com .
Notes
UDC Summary (abridged web edition) – published in 2009 – available for free from http://www.udcc.org/udcsummary/php/index.php
- – UDC Online (complete web edition) – published in August 2013 – available under annual subscription from http://www.udc-hub.com/en/login.php
– Abridged UDC Edition (printed) – in preparation – planned for September 2014 – Complete UDC Edition (printed) – planned for 2015
Learn More:
Module LIS/KOP – C/12(3): UDC
1. Do you know
- UDC is the first truly international classification designed by an international organisation then IIB/IID, later FID, now defunct. Since January 1992 it is managed by the UDCC.
- It is the first multilingual classification officially published in three languages, namely French, German and English in order. Now English is the main language in which its MRF is created.
- It is one of the three major classification of the world, the other two being DDC and LCC.
- Technically it is superior of the trio.
2. Points to remember
- It was the first bibliographic classification designed not to arrange books in a library but to arrange entries in a bibliography – in fact a universal bibliography.
- Many library historians consider it the first faceted classification though it did not use the term as such.
- Earlier it was available in three editions of details: Full, Medium and Abridged; now it is only in Abridged and Standard editions.
- Its summary of 1000 classes is available in open access in about 40 languages of the world including many Indian languages.
- Professor Ia. C. McIlwaine of the School of Librarianship and Archives, University College, London was the first full time editor (1993-2006).
- Its current editor is Dr. Aida Slavic.
- Its editorial office is in the Royal (National) Library of the Netherlands, at the Hague.
- Among other web sources the UDC is used to organise and search the Directory of Networked Resources (www.niss.ac.uk) of the (UK) National Information Services and Systems (NISS).
- All editions of the UDC are derived from the electronic Master Reference File (MRF).