Library classification
Encyclopedia
A library classification is a system
of coding and organizing document
s or library materials (book
s, serials, audiovisual materials, computer files, map
s, manuscript
s, 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 together that are similar, typically arranged in a hierarchical tree structure. A different kind of classification system, called a faceted classification
system, is also widely used which allows the assignment of multiple classifications to an object, enabling the classifications to be ordered in multiple ways.
. It is a form of bibliographic classification (library classifications are used in library catalogs, while "bibliographic classification" also covsometimes grouped together as technical services. The library professional who engages in the process of cataloging and classifying library materials is called a cataloguer or catalog librarian. Library classification systems are one of the two tools used to facilitate subject access
. The other consists of
Library classification of a piece of work consists of two steps. Firstly, the "aboutness" of the material is ascertained. Next, a call number (essentially a book's address) based on the classification system in use at the particular library will be assigned to the work using the notation of the system.
It is important to note that unlike subject heading or thesauri where multiple terms can be assigned to the same work, in library classification systems, each work can only be placed in one class. This is due to shelving purposes: A book can have only one physical place. However in classified catalogs one may have main entries as well as added entries. Most classification systems like the Dewey Decimal Classification
(DDC) and Library of Congress classification
also add a cutter number to each work which adds a code for the author of the work.
Classification systems in libraries generally play two roles. Firstly, they facilitate subject access
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.
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 faceted 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.
In terms of functionality, classification systems are often described as:
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
.
The above systems are the most common in the English
-speaking world.
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.
System
System is a set of interacting or interdependent components forming an integrated whole....
of coding and organizing document
Document
The term document has multiple meanings in ordinary language and in scholarship. WordNet 3.1. lists four meanings :* document, written document, papers...
s or library materials (book
Book
A book is a set or collection of written, printed, illustrated, or blank sheets, made of hot lava, paper, parchment, or other materials, usually fastened together to hinge at one side. A single sheet within a book is called a leaf or leaflet, and each side of a leaf is called a page...
s, serials, audiovisual materials, computer files, map
Map
A map is a visual representation of an area—a symbolic depiction highlighting relationships between elements of that space such as objects, regions, and themes....
s, manuscript
Manuscript
A manuscript or handwrite is written information that has been manually created by someone or some people, such as a hand-written letter, as opposed to being printed or reproduced some other way...
s, realia
Realia (library science)
In library classification systems, the term realia refers to three-dimensional objects from real life such as coins, tools, and textiles, that do not easily fit into the orderly categories of printed material...
) 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 together that are similar, typically arranged in a hierarchical tree structure. A different kind of classification system, called a faceted classification
Faceted classification
A faceted classification system allows the assignment of multiple classifications to an object, enabling the classifications to be ordered in multiple ways, rather than in a single, predetermined, taxonomic order. A facet comprises "clearly defined, mutually exclusive, and collectively exhaustive...
system, is also widely used which allows the assignment of multiple classifications to an object, enabling the classifications to be ordered in multiple ways.
Description
Library classification form part of the field of library and information scienceLibrary and information science
Library and information science is a merging of the two fields library science and information science...
. It is a form of bibliographic classification (library classifications are used in library catalogs, while "bibliographic classification" also covsometimes grouped together as technical services. The library professional who engages in the process of cataloging and classifying library materials is called a cataloguer or catalog librarian. Library classification systems are one of the two tools used to facilitate subject access
Subject access
Subject access refers to the methods and systems by which books, journals, and other documents are accessed in a given bibliographic database . The single records in a bibliographic file is structured in fields and each field can be searchable and combined with other fields. Such searchable data...
. The other consists of
Library classification of a piece of work consists of two steps. Firstly, the "aboutness" of the material is ascertained. Next, a call number (essentially a book's address) based on the classification system in use at the particular library will be assigned to the work using the notation of the system.
It is important to note that unlike subject heading or thesauri where multiple terms can be assigned to the same work, in library classification systems, each work can only be placed in one class. This is due to shelving purposes: A book can have only one physical place. However in classified catalogs one may have main entries as well as added entries. Most classification systems like the Dewey Decimal Classification
Dewey Decimal Classification
Dewey Decimal Classification, is a proprietary system of library classification developed by Melvil Dewey in 1876.It has been greatly modified and expanded through 23 major revisions, the most recent in 2011...
(DDC) and Library of Congress classification
Library of Congress Classification
The Library of Congress Classification is a system of library classification developed by the Library of Congress. It is used by most research and academic libraries in the U.S. and several other countries; for example, Australia and Taiwan, R.O.C. It is not to be confused with the Library of...
also add a cutter number to each work which adds a code for the author of the work.
Classification systems in libraries generally play two roles. Firstly, they facilitate subject access
Subject access
Subject access refers to the methods and systems by which books, journals, and other documents are accessed in a given bibliographic database . The single records in a bibliographic file is structured in fields and each field can be searchable and combined with other fields. Such searchable data...
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
Library catalog
A library catalog is a register of all bibliographic items found in a library or group of libraries, such as a network of libraries at several locations...
. 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.
Some classification systems are more suitable for aiding subject access, rather than for shelf location. For example, UDC
Universal Decimal Classification
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. It is based on the Dewey Decimal Classification, but uses auxiliary signs to indicate various special aspects of a...
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 faceted classification
Faceted classification
A faceted classification system allows the assignment of multiple classifications to an object, enabling the classifications to be ordered in multiple ways, rather than in a single, predetermined, taxonomic order. A facet comprises "clearly defined, mutually exclusive, and collectively exhaustive...
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.
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 ClassificationDewey Decimal ClassificationDewey Decimal Classification, is a proprietary system of library classification developed by Melvil Dewey in 1876.It has been greatly modified and expanded through 23 major revisions, the most recent in 2011...
, Universal Decimal ClassificationUniversal Decimal ClassificationThe 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. It is based on the Dewey Decimal Classification, but uses auxiliary signs to indicate various special aspects of a...
and Library of Congress ClassificationLibrary of Congress ClassificationThe Library of Congress Classification is a system of library classification developed by the Library of Congress. It is used by most research and academic libraries in the U.S. and several other countries; for example, Australia and Taiwan, R.O.C. It is not to be confused with the Library of...
- Specific classification schemes for particular subjects or types of materials. Examples include Iconclass, British Catalogue of Music Classification, and Dickinson classificationDickinson classificationThe Dickinson classification is a library classification scheme used to catalogue and classify musical compositions. It was developed by George Sherman Dickinson , and is used by many music libraries, primarily those at University at Buffalo, Vassar, and Columbia Universities.It is fully detailed...
, or the NLM Classification for medicine.
- National schemes specially created for certain countries. An example is the SwedishSwedenSweden , officially the Kingdom of Sweden , is a Nordic country on the Scandinavian Peninsula in Northern Europe. Sweden borders with Norway and Finland and is connected to Denmark by a bridge-tunnel across the Öresund....
library classification system, SAB (Sveriges Allmänna Biblioteksförening).
In terms of functionality, classification systems are often described as:
- enumerativeEnumerationIn mathematics and theoretical computer science, the broadest and most abstract definition of an enumeration of a set is an exact listing of all of its elements . The restrictions imposed on the type of list used depend on the branch of mathematics and the context in which one is working...
: subject headings are listed alphabetically, with numbers assigned to each heading in alphabetical order. - hierarchicalHierarchyA hierarchy is an arrangement of items in which the items are represented as being "above," "below," or "at the same level as" one another...
: subjects are divided hierarchically, from most general to most specific. - facetedFaceted classificationA faceted classification system allows the assignment of multiple classifications to an object, enabling the classifications to be ordered in multiple ways, rather than in a single, predetermined, taxonomic order. A facet comprises "clearly defined, mutually exclusive, and collectively exhaustive...
or analytico-synthetic: subjects are divided 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
Colon classification
Colon classification is a system of library classification developed by S. R. Ranganathan. It was the first ever faceted classification. The first edition was published in 1933. Since then six more editions have been published...
of S. R. Ranganathan
S. R. Ranganathan
Shiyali Ramamrita Ranganathan was a mathematician and librarian from India. His most notable contributions to the field were his five laws of library science and the development of the first major analytico-synthetic classification system, the colon classification...
.
Universal classification systems used in the English-speaking world
- Dewey Decimal ClassificationDewey Decimal ClassificationDewey Decimal Classification, is a proprietary system of library classification developed by Melvil Dewey in 1876.It has been greatly modified and expanded through 23 major revisions, the most recent in 2011...
(DDC) - Library of Congress ClassificationLibrary of Congress ClassificationThe Library of Congress Classification is a system of library classification developed by the Library of Congress. It is used by most research and academic libraries in the U.S. and several other countries; for example, Australia and Taiwan, R.O.C. It is not to be confused with the Library of...
(LCC) - Bliss bibliographic classificationBliss bibliographic classificationThe Bliss bibliographic classification is a library classification system that was created by Henry E. Bliss , published in four volumes between 1940 and 1953. Although originally devised in the United States, it was more commonly adopted by British libraries than by American ones...
(BC)
The above systems are the most common in the English
English language
English is a West Germanic language that arose in the Anglo-Saxon kingdoms of England and spread into what was to become south-east Scotland under the influence of the Anglian medieval kingdom of Northumbria...
-speaking world.
- BISAC Subject Headings: The publishing industry standard for classification that is being adopted by some libraries.
- Harvard-Yenching ClassificationHarvard-Yenching ClassificationAlfred Kaiming Chiu was a pioneer of establishing a library classification system for Chinese language materials in the United States of America. The system devised by him was known as Harvard–Yenching Classification System...
: An English classification system for Chinese language materials. - V-LIB 1.2 (2008 Vartavan Library Classification for over 700 fields of knowledge, currently sold under license in the UK by Rosecastle Ltd. (see http://rosecastle.atspace.com/index_files/Page382.html).
Universal classification systems in other languages
- A system of book classification for Chinese libraries (Liu's Classification) library classification for user
- New Classification Scheme for Chinese LibrariesNew Classification Scheme for Chinese LibrariesThe New Classification Scheme for Chinese Libraries is a system of library classification developed by Yung-Hsiang Lai since 1956. It is modified from "A System of Book Classification for Chinese Libraries" of Liu Guojun, which is based on the Dewey Decimal System.The scheme is developed for...
- New Classification Scheme for Chinese Libraries
- Nippon Decimal ClassificationNippon Decimal ClassificationThe Nippon Decimal Classification is a system of library classification developed for mainly Chinese and Japanese language books maintained by the Japan Library Association since 1956. It is based on the Dewey Decimal System...
(NDC) - Chinese Library ClassificationChinese Library ClassificationThe Chinese Library Classification , also known as Classification for Chinese Libraries , is effectively the national library classification scheme in China. It is used in almost all primary and secondary schools, universities, academic institutions, as well as public libraries...
(CLC) - Korean Decimal ClassificationKorean Decimal ClassificationThe Korean Decimal Classification is a system of library classification used in Korea. The main classes are the same as in the Dewey Decimal Classification but these are in a different order: Natural sciences 400; Technology and engineering 500; Arts 600; Language 700.-Main classes:* 000 General*...
(KDC) - Library-Bibliographic Classification (BBK) from Russia.
Universal classification systems that rely on synthesis (faceted systems)
- Bliss bibliographic classificationBliss bibliographic classificationThe Bliss bibliographic classification is a library classification system that was created by Henry E. Bliss , published in four volumes between 1940 and 1953. Although originally devised in the United States, it was more commonly adopted by British libraries than by American ones...
- Colon classificationColon classificationColon classification is a system of library classification developed by S. R. Ranganathan. It was the first ever faceted classification. The first edition was published in 1933. Since then six more editions have been published...
- Cutter Expansive ClassificationCutter Expansive ClassificationThe Cutter Expansive Classification system is a library classification system devised by Charles Ammi Cutter. The system was the basis for the top categories of the Library of Congress Classification.-History of the Expansive Classification:...
- Universal Decimal ClassificationUniversal Decimal ClassificationThe 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. It is based on the Dewey Decimal Classification, but uses auxiliary signs to indicate various special aspects of a...
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.
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 accommodate 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
- Usability
See also
- Document classificationDocument classificationDocument classification or document categorization is a problem in both library science, information science and computer science. The task is to assign a document to one or more classes or categories. This may be done "manually" or algorithmically...
- Library managementLibrary managementLibrary management is a sub-discipline of institutional management that focuses on specific issues faced by libraries. Library management encompasses normal management tasks as well as intellectual freedom, anti-censorship, and fundraising tasks...
- CategorizationCategorizationCategorization is the process in which ideas and objects are recognized, differentiated and understood. Categorization implies that objects are grouped into categories, usually for some specific purpose. Ideally, a category illuminates a relationship between the subjects and objects of knowledge...
- Knowledge organizationKnowledge organizationThe term knowledge organization designates a field of study related to Library and Information Science . In this meaning, KO is about activities such as document description, indexing and classification performed in libraries, databases, archives etc...
- Library of Congress Subject HeadingsLibrary of Congress Subject HeadingsThe Library of Congress Subject Headings comprise a thesaurus of subject headings, maintained by the United States Library of Congress, for use in bibliographic records...
- Attribute-value systemAttribute-value systemAn attribute-value system is a basic knowledge representation framework comprising a table with columns designating "attributes" and rows designating "objects" An attribute-value system is a basic knowledge representation framework comprising a table with columns designating "attributes" (also...