Genesis: Basis for Early Development

A significant aspect of modern classification relates to the theories dealing with arrangement and order of subclasses. Ranganathan introduced the concept of "facets" in the Colon Classification system, and these facets are defined as "trains or characteristics."

For example, a subject like literature contains four facets or components: author, language, form, and work characteristics. Thus, other classes would logically have different and unique numbers of facets. The "formal ordering of subclasses into postulates or orders such as chronological, canonical, geographical, etc.," is a theory developed by Ranganathan. The main contribution he has made, "at least to the Western classification theory has been the principle of faceting" (Painter 1972).

Ranganathan asserts: "Classification is an uncovering of the thought-content of a written or expressed unit of thought... [a] librarian applies the classification scheme in the ultimate stage of library service which is effecting contact between the right reader and the right unit of thought in a personal way." The first general scheme to contain a degree of faceted structure was the Universal Decimal Classification (UDC). Faceted classification is also termed as analytico-synthetic. The later name describes the two main processes involved in the creation of a call number:

• Analysis: Breaking down and separating each subject into its basic ideas and concepts.
• Synthesis: Merging or connecting the relevant units and concepts to describe the subject matter of the information package in hand.

Ranganathan believed classification could be summed up as the "idea plane, the verbal plane, and the notational plane." According to his definition, classification is: "a method by which a written or expressed unit of thought is exhaustively analyzed in terms of entirety rather than in terms of parts." Two important assemblies of classification experts, one at Dorking, England 1957, and the other at Elsinore, Denmark 1964, have provided very valuable definitions on classification worth studying. The latter group of experts from Dorking England gives this definition about classification:

"Traditional classification has been concerned with the construction of hierarchies of terms - chains of classes and coordinate arrays. Modern information retrieval techniques also necessitate the combination of terms to express complex subjects...All intellectual organization is classification, and such things as alphabetical indexing or numerical arrays are species of classification" (Ibid.).