Colon Classification : A brief Information About Library Colon Classification

Classification English General Library Science

Colon Classification

Colon Classification is one of the most systematic schemes of Library Classifications used in many libraries in India and a few libraries abroad as well. This was devised by the late Dr. S.R. Ranganathan. He found the existing scheme of library classification unable to cope with the multidimensional dynamic growth of universe of subjects. Colon Classification proceeds in a different manner in spite of enumerating all possible subjects and their sub-divisions, it analyses the subject in its various components and places them under five fundamental categories known as personality, matter, energy, space and time. To connect or to synthesize the various components of a subject, different connection symbols have been provided. Readymade class numbers are also available, but to build a class number, one has to analyze and pick up the possible isolates belonging to different fundamental categories which are then put together with the help appropriate connecting symbols. Colon Classification involves analysis and synthesis that is why it is known as the ‘Analytico-synthetic’ scheme of classification. The number building makes the scheme somewhat complicated and difficult to work with, but once understood and followed it works efficiently and effectively. The Colon Classification is a general scheme which aims to classify by subject all kinds of documents- books, periodicals, reports, pamphlets, microforms and electronic media in all kinds of libraries. CC is al andmark in the modern classification thought and has greatly influenced the modern classification research and developments.

1.1 Colon Classification:

Colon Classification (CC) is the brain – child of Shiyali Rarnamrita Ranganathan. It was first published in the year 1933 (Ranganathan, 1933). Till now seven editions of CC have been published. The seven editions as per their features are grouped in three groups called versions (Gopinath, 1976).

Version 1- Rigidly faceted classification schemes: First, second and third editions of CC belong to this version. Editions of this version used only one facet indicator digit i.e. Colon (:). That is the reason it got the name Colon Classification. Editions belonging to this version gave short schedules of basic subjects, few common isolates and a large number of special isolates.

Version 2- Almost freely faceted classification schemes: Fourth, the fifth and sixth edition of CC belong to this version. This version is called as almost freely faceted version because it used different facet indicator digits for different facets such as:

             Facet                                    Indicator digit used

i. Personality                                , (Comma)

ii. Matter                                       ; (Semi-colon)

iii. Energy                                     : (Colon)

iv. Space                                      . (Dot)

v. Time                                         ‘ (Single inverted comma)

Editions of this version of CC also introduced the concept of Rounds and Levels to remove the severe rigidity.

Version 3 – Freely faceted classification schemes: Seventh edition of CC (Ranganathan, 1987) published in the year 1987 represents the third version. This edition incorporates findings of a dynamic theory of classification (Gopinath, 1976). Being a freely faceted classification scheme it has no rigid formula for compound subject going with the basic subject.

1.1.1 The postulational approach: The universe of subjects as represented by documents is multidimensional. However, the documents can be arranged on the library shelves only in a linear manner. It is difficult to arrange the multidimensional universe of subjects in an uni-dimensional way. To overcome this difficulty Ranganathan resorted to the postulational approach.

‘A postulate is a statement about which we cannot use either of the epithets ‘right’ or ‘wrong’. We can only speak of a set of postulate as helpful or unhelpful’ (Ranganathan, 1962). Gopinath discusses postulational approach and believes that it has provided objectivity and scientific basis to CC (Gopinath, 1986). M. M. Kashyap reviews development and impact of postulational approach (Kashyap, 1986).

1.1.2 Postulate of Fundamental Categories: Ranganathan has based his CC on many postulates. The postulate of fundamental categories is one of them. According to Ranganathan there are five and only five fundamental categories- viz. Time, Space, Energy, Matter and Personality, which are defined by enumeration only (Ranganathan, 1989d). The number of categories, however, differ from person to person (Seetharama, 1972). These categories being postulates have no scientific justification but are extremely useful in library classification. Ranganathan not only enumerated the fundamental categories but also recommended their sequence as PMEST. Hemalata Iyer analyzes this sequence in the context of user preferences. (Iyer, 1986). Based on the fundamental categories, Ranganathan developed the concept of facet analysis. Facet analysis is useful in designing faceted / analytico-synthetic classification schemes. Facet analysis has many more applications which are described by Devadasan (1986). The terms representing fundamental categories may have different meanings in different subjects, however Ranganathan used them with a specific context i.e. Personality: Personality covers manifestations of wholeness, for example, chemical compounds, plants and animals and parts of them, languages religions, etc. The other Fundamental Categories are attributes of Personality.

Without Personality, there can be no organ, constituent, attribute, action, reaction or incidence in space and time. Personality forms the basis, the host, locus of all other categories. In the main class ‘library and information science’ (LIS) concepts like libraries, information sources, library personnel, and users form the locus to the other fundamental categories. That is the reason these isolates belong to the fundamental category, Personality.

The fundamental category, Personality presents great difficulty in its identification. It is too elusive. It is ineffable (Ranganathan, 1989e). As it is difficult to identify the fundamental category, Personality, Ranganathan suggested the ‘method of residues’ for its identification.

Norman Roberts provides a definitional analysis of Personality and discusses the limitations of this concept (Roberts, 1969). Foskett (1961) and Grolier (1962) provide a critical evaluation of Personality. Matter: Since the recent past name of the fundamental category Matter is replaced by Matter Property [MP]. Initially, as Ranganathan claimed this fundamental category represented materials only. Later on two more manifestations of this category were identified, i.e. Matter Property and Matter Method. (Ranganathan, 1971). Library activities like classification, cataloguing, circulation, etc. for example, represent the property of the Personality of the library. So they belonged to Matter facet. The fundamental category Matter Method mostly manifests in science and technology subjects. For example in the main class ‘geology’ isolates like ‘mechanical, seismological’, etc. manifest as Matter Method isolates. Neelameghan and Gopinath (1967) discuss the problems in grouping of [MP] isolates and solutions thereto. Energy: The fundamental category, Energy represents action. The action may be among and by all kinds of entities- inanimate, animate, conceptual, intellectual and intuitive (Ranganathan, 1989f). In the main class ‘library science’ computerization, preservation, management, etc. are examples of the manifestation of the fundamental category, Energy. Space and Time: The fundamental category ‘Space’ represents the geographical area and ‘Time’ represents period.

1.1.3 Postulates of rounds and levels: Recurring manifestation of the aforementioned fundamental categories is required for classifying subjects of greater intention. This need is fulfilled by postulates of rounds and levels. Postulate of rounds: According to this postulate the fundamental category, Personality, Matter and Energy may manifest itself in one and the same subject more than once (Ranganathan, 1989g). Ordinarily, the fundamental categories, Space and Time may manifest only once in the last round. Postulate of levels: According to this postulate the fundamental category, Personality and Matter may manifest itself more than once in one and the same round within a subject (Ranganathan, 1989g).

1.1.4 Postulate of quasi-isolate: Name of the characteristics used to represent an isolated idea or a spectator is called quasi-isolate (QI). It is so called because it does not represent a true isolate idea, e.g. the ‘Personality’ isolates of the main class ‘Sociology’ in the seventh edition of CC are first represented as (QI). These are for example, ‘By age’, ‘By residence’, etc. (Ranganathan, 1987b). Similarly in the main class `Educational Psychology’ the speciators are grouped under various quasi isolates (QIs) (Ranganathan, 1987c). Some times a particular facet may have a large number of (QIs). When the number of (QIs) is large the problem of their ranking arises. As a solution to this Neelameghan and Gopinath (1966) suggested ‘Group Strategy’. Group strategy is a useful method for grouping (QIs).

1.1.5 Postulate of speciator: Speciator is an isolated idea used as a qualifier for an isolate or another speciator. When a sub isolate i.e. a qualifier to an isolate, has a possibility of going with more than one isolates, it is listed as speciator, instead of chain division, e. g. the sub isolate ‘computerized’ can go with the isolates such as cataloguing, classification, circulation, etc. As such the sub isolate ‘computerized’ is listed as a speciator, only once, and can be combined with any appropriate isolate as and when needed to form class number for a compound subject. Kinds of speciators: There are two kinds of speciators. Speciator kind 1 (Spl) qualifies an isolate idea, e.g. ‘branch’ a (Spl ) may qualify the isolate ‘library’ in the main class LIS to represent the subject ‘branch library’. The connecting symbol hyphen (-) is used to connect the speciator kind I to an isolate.

Speciator kind 2 (Sp2) qualifies the speciator kind 1, e.g. ‘abstracting sources’ is a speciator kind 1. It qualifies the isolate idea information sources. The proper name Library and Information Science Abstracts (LISA) is speciator kind 2, as it qualifies the speciator kind I ‘abstracting sources’. Speciator kind 2 are attached to speciator kind 1 by using the connecting symbol ‘equal to’ (=). Neelameghan and Gopinath (1973) provide meaning and use of (Sp2) through a case study.

History of Colon Classification:

Shiyali Ramamrita Ranganathan, the author of Colon Classification began his career as a teacher of mathematics. However in 1924, he was appointed Librarian of the University of Madras. He went to England in 1924 to study library science at the University of London, School of Librarianship. Dissatisfied with the existing schemes of library classification, his experience led him “to think that a change was necessary in the basic principles on which schemes of classification are established. While in London, Ranganathan designed a layout for the new scheme and constructed the schedules of a few subjects for different facets as samples. In about a year, he found the colon device to be extremely useful. With the help of few subject specialists, the schedules were completed in 1927. In 1932, the scheme was ready to be printed. Thus, in 1933, the first edition of colon classification was released. Till now, six editions including the reprinting of 6th edition, published in 1963of CC have been published.Colon Classification
Different Editions of Colon Classification:
The Colon Classification (CC) first designed from 1924 to 1928 and published first in 1933 by the Madras Library Association is now in its 7th edition released in 1987. The sixth edition still the most popular one was published in 1960. A reprint with some amendments contained in an an nexure was issued in 1963. This manual aiming to be a guide to the use of CC -6, explains the construction of class numbers by this edition (1963) which was reprinted in 1964 and 1969 by its publishers Asia Publishing House Bombay. Since 1989 this edition with annexure has been reprinted many times by the Sarda Ranganathan Endowment for Library Science.
1st Edition1933
2st Edition1939
3rd Edition1950
4th Edition1952
5th Edition1957
6th Edition1960
7th Edition1987

Notational System:

The Notational System of Colon Classification used for assigning numbers to basic subjects consists of:

  • 23 Roman small letters (a…z excluding i, l, o)
  • 10 Indo Arabic numerals (0-9)
  • 26 Roman Capital letters (A–Z)
  • Bracketed numbers
  • Indicator digit hyphen (-) and asterisk (*)

Z, 0 (zero) or 9 (nine) is used to represent an empty digit. T,V,X & Z are used as emptying digits, however, when these occur as an initial digit, then they are deemed semantically rich digit. U,W, & Y have been postulated as empty-emptying digit.

The notational system used by CC to assign numbers to isolate as speciators consist of the following:

  1. Ten Indo-Arabic numerals(0—9)
  2. Twenty Six Roman capital letters (A—Z)
  3. Twenty Six Roman small letters (a—z excluding i, l, o)
  4. Bracketed Numbers
  5. Indicator digits * ” ← ) & ‘ . ; ,-= + → (

Colon Classification Index:

The index of CC refers only to elementary terms, never to compound subjects. The relative aspects of a subject are provided only in the form of class numbers, not being named as in DDC or UDC. CC6 has provided the following four indexes: General Index; Geographical Index; Two Indexes to Natural Groups in Botany and Zoology. The entrieshave been arranged by word by word order following the principle of nothing before something.

Reference Article:

  • Kumbhar, R. M. (2003). Contruction of vocabulary control tool thesaurus for library and information science.

Related Articles:

 This Video Tutorial can help you to know more about Colon Classification.


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