Library classification forms part of the field of library and information science. It goes hand in hand with library (descriptive) cataloging under the rubric of cataloging and classification, sometimes grouped together as technical services. The library professional who engages in the process of cataloging and classifying library materials is called a cataloger or catalog librarian. Library classification systems are one of the two tools used to facilitate subject access. The other are alphabetical indexing languages such as Thesaurui and Subject Headings systems. Library and information science (LIS) is the study of issues related to libraries and the information fields. ...

A library classification is a system of coding and organizing library materials (books, serials, audiovisual materials, computer files, maps, manuscripts, realia) according to their subject and allocating a call number to that information resource. Similar to classification systems used in biology, bibliographic classification systems group entities that are similar together typically arranged in a hierarchical tree structure (assuming none-faceted system). For other uses, see System (disambiguation). ... For other uses, see Book (disambiguation). ... For other uses, see Map (disambiguation). ... A manuscript (Latin manu scriptus, written by hand), strictly speaking, is any written document that is put down by hand, in contrast to being printed or reproduced some other way. ... In library classification systems, realia are objects such as coins, tools, games, toys, or other physical objects that do not easily fit into the neat categories of books, periodicals, sound recordings, or the like. ...

Classification of a piece of work consists of two steps. Firstly the 'aboutness' of the material is ascertained. Next, a call number based on the classification system will be assigned to the work using the notation of the system.

It is important to note that unlike subject heading or Thesaurui where multiple terms can be assigned to the same work, in classification systems, each work can only be placed in one class. This is true also for faceted (see later) classification systems due to the enforcement of a citation order. Most classification systems like DDC and Library of Congress classification, also add a cutter number to each work which adds a code for the author of the work. The Cutter Expansive Classification system is a library classification system devised by Charles Ammi Cutter. ...

Classification systems in libraries generally play two roles. Firstly they facilitate subject access (See Cutter) by allowing the user to find out what works or documents the library has on a certain subject. Secondly, they provide a known location for the information source to be located (e.g where it is shelved).

Until the 19th century, most libraries had closed stacks, so the library classification only served to organize the subject catalog. In the 20th century, libraries opened their stacks to the public and started to shelve the library material itself according to some library classification to simplify subject browsing. Alternative meaning: Nineteenth Century (periodical) (18th century — 19th century — 20th century — more centuries) As a means of recording the passage of time, the 19th century was that century which lasted from 1801-1900 in the sense of the Gregorian calendar. ... The card catalog at Yale Universitys Sterling Memorial Library goes almost completely unused, but adds to the austere atmosphere. ... (19th century - 20th century - 21st century - more centuries) Decades: 1900s 1910s 1920s 1930s 1940s 1950s 1960s 1970s 1980s 1990s As a means of recording the passage of time, the 20th century was that century which lasted from 1901–2000 in the sense of the Gregorian calendar (1900–1999...

Some classification systems are more suitable for aiding subject access, rather than for shelf location. For example, UDC which uses a complicated notation including plus, colons are more difficult to use for the purpose of shelf arrangement but are more expressive compared to DDC in terms of showing relationships between subjects. Similarly facteted classification schemes are more difficult to use for shelf arrangement, unless the user has knowledge of the citation order.

Depending on the size of the library collection, some libraries might use classification systems solely for one purpose or the other. In extreme cases a public library with a small collection might just use a classification system for location of resources but might not use a complicated subject classification system. Instead all resources might just be put into a couple of wide classes (Travel, Crime, Magazines etc). This is known as a "mark and park" classification method, more formally called reader interest classification ^[1]

Types

There are many standard systems of library classification in use, and many more have been proposed over the years. However in general, Classification systems can be divided into three types depending on how they are used.

• Universal schemes covering all subjects. Examples include Dewey Decimal Classification and Library of Congress Classification

• Specific classification schemes. Examples includes Iconclass, British classification of Music

• National schemes specially created for certain countries. Example is SAB.

In terms of functionality, classification systems are often described as

• enumerative: produce an alphabetical list of subject headings, assign numbers to each heading in alphabetical order
• hierarchical: divides subjects hierarchically, from most general to most specific
• faceted or analytico-synthetic: divides subjects into mutually exclusive orthogonal facets

There are few completely enumerative systems or faceted systems, most systems are a blend but favouring one type or the other. The most common classification systems, LCC and DDC, are essentially enumerative, though with some hierarchical and faceted elements (more so for DDC), especially at the broadest and most general level. The first true faceted system was the Colon classification of S. R. Ranganathan. In mathematics and theoretical computer science, an enumeration of a set is a procedure for listing all members of the set in some definite sequence. ... A hierarchy (in Greek: , derived from — hieros, sacred, and — arkho, rule) is a system of ranking and organizing things or people, where each element of the system (except for the top element) is subordinate to a single other element. ... A faceted classification system allows the assignment of multiple classifications to an object, allowing searching and browsing of related information through several classes. ... Colon classification (CC) is a system of library classification developed by S. R. Ranganathan. ... Shiyali Ramamrita Ranganathan (August 9, 1892, Shiyali, Tamil Nadu - September 27, 1972, Bangalore) was an innovative mathematician and librarian from India. ...

Specific classification systems used in English-speaking world

• Bliss bibliographic classification (BC)
• Dewey Decimal Classification (DDC)
• Library of Congress Classification (LC)
• Dickinson classification

(The above systems are the most common in the English-speaking world.) The Bliss bibliographic classification is a library classification system and is known as BC. It is originally developed by Henry E. Bliss and first published in four volumes in the USA between 1940 and 1953. ... The Dewey Decimal Classification (DDC, also called the Dewey Decimal System) is a proprietary system of library classification developed by Melvil Dewey in 1876, and has since then been greatly modified and expanded through twenty-two major revisions, the most recent in 2004. ... Library of Congress reading room The Library of Congress Classification (LCC) is a system of library classification developed by the Library of Congress. ... The Dickinson classification is a library classification scheme used to catalogue and classify musical compositions. ... The English language is a West Germanic language that originates in England. ...

• Harvard-Yenching Classification - An English classification system for Chinese language materials.

Alfred Kaiming Chiu (1898-1977) was a pioneer of establishing a library classification system for Chinese language materials in the United States of America. ...

Specific classification systems in other languages

• Nippon Decimal Classification (NDC)
• Chinese Library Classification (CLC)
• Korean Decimal Classification (KDC)

The Nippon Decimal Classification (NDC, also called the Nippon Decimal System) is a system of library classification developed for mainly Chinese and Japanese language books maintained by the Japan Library Association since 1956. ... The Chinese Library Classification (CLC), also known as Classification for Chinese Libraries (CCL) is a library classification that is currently widely used in almost all of the libraries of primary and secondary schools, academic institutions, colleges, universities as well as public libraries throughout Mainland China in the Peoples Republic... The Korean Decimal Classification (KDC) is a system of library classification used in Korea. ...

Specific classification systems that rely on synthesis (faceted systems)

• Bliss bibliographic classification
• Colon classification
• Cutter Expansive Classification
• Universal Decimal Classification
• Brinkler classification

Newer classification systems tend to use the principle of synthesis (combining codes from different lists to represent the different attributes of a work) heavily, which is comparatively lacking in LC or DDC. The Bliss bibliographic classification is a library classification system and is known as BC. It is originally developed by Henry E. Bliss and first published in four volumes in the USA between 1940 and 1953. ... Colon classification (CC) is a system of library classification developed by S. R. Ranganathan. ... The Cutter Expansive Classification system is a library classification system devised by Charles Ammi Cutter. ... The Universal Decimal Classification is a system of library classification developed by the Belgian bibliographers Paul Otlet and Henri la Fontaine at the end of the 19th century. ... Please wikify (format) this article as suggested in the Guide to layout and the Manual of Style. ...

Comparing Classification Systems

As a result of differences in Notation, history, use of enumeration, hierarchy, facets, classification systems can differ in the following ways

• Type of Notation - Notation can be pure (consisting of only numerals for example) or mixed (consisting of letters, numerals, and other symbols).

• Expressiveness - This is the degree in which the notation can express relationship between concepts or structure.

• Whether they support mnemonics - For example the number 44 in DDC notation usually means it concerns some aspect of France. For example 598.0944 concerns "Birds in France". the 09 signifies country code, and 44 represents France.

• Hospitality - The degree in which the system is able to accommodates new subjects

• Brevity - Length of the notation to express the same concept

• Speed of updates and degree of support - The best classification systems are constantly being reviewed and improved.

• Consistency

• Simplicity

See also

• Categorization

For Wikipedias categorization projects, see Wikipedia:Categorization. ...

References

External links

• An annotated bibliography on Library Classification and Subject Approaches to Information - by Salman Haider, Librarian (Cataloging), US Library of Congress, New Delhi Overseas Office
• A Preview of the New Cataloging Code