The three major universal Standard Schemes of Classification, namely Colon Classification (CC), Dewey Decimal Classification (DDC), and Universal Decimal Classification (UDC), are fundamental tools used for organizing knowledge and library materials. They differ significantly in their historical development, structure, notation, and methodology.
Here is an overview of the features of these three schemes:
I. Dewey Decimal Classification (DDC)
The Dewey Decimal Classification (DDC), conceptualized by Melvil Dewey and first published in 1876, is currently one of the most popular and widely used library classification schemes globally. It has undergone numerous revisions, with the most recent major revision (DDC 23) occurring in 2011.
| Feature | Description | Source Details |
|---|---|---|
| Type | Originally devised as an Enumerative Scheme, DDC is often described as an almost-enumerative classification. It has absorbed the structure and methodology of faceted classification in subsequent revisions. | |
| Structure | It attempts to organize all knowledge into ten main classes. These ten main classes are hierarchically subdivided into 100 divisions and 1,000 sections. | |
| Basis of Order | DDC is a discipline-oriented classification. The arrangement follows a decimal system. | |
| Notation | Uses purely numerical notation (Arabic numerals 0–9). Each base number has a minimum of three digits, with further divisions following a decimal point (.). | |
| Synthesis/Flexibility | Although largely enumerative, DDC utilizes subsidiary tables and 'divide like' devices that reflect and can express many aspects of complex topics. It currently utilizes seven auxiliary tables. | |
| Usage | DDC is used in approximately 200,000 libraries in at least 135 countries. It is often suitable for browsing by library users. | |
| Weaknesses | Its reliance on a top-down approach makes it difficult to adapt to changing fields of knowledge. Notations can be much longer compared to other systems. It has problems with overlapping in classes like Engineering (620) and Arts (700). | |
| Availability | Published in full and abridged editions in print and electronic versions (e.g., Web Dewey). |
II. Universal Decimal Classification (UDC)
The Universal Decimal Classification (UDC) was developed by Paul Otlet and Henri La Fontaine at the end of the 19th century, taking the DDC as its base. It is an improvement upon the original DDC scheme.
| Feature | Description | Source Details |
|---|---|---|
| Type | Though basically enumerative, UDC is characterized by a significant faceted or analytic-synthetic element. It is classified as an Almost-Faceted Classification. | |
| Structure | It is a general classification covering the whole domain of knowledge. It borrowed its basic structure from DDC, with the exception of merging main classes 4 and 8 (Language and Literature), leaving Main Class 4 vacant. | |
| Basis of Order | Classifications use Arabic numerals and are based on the decimal system. Every number is treated as a decimal fraction, which determines filing order. | |
| Notation | Uses a mixed notation of decimal numbers, punctuation signs, and symbols. It uses auxiliary signs (like colon, parentheses, etc.) to indicate various aspects and relationships between subjects. | |
| Synthesis/Flexibility | It is a synthetic classification with a powerful auxiliary apparatus of relations and synthesis. It uses two types of auxiliary tables: Common Auxiliaries (universally applicable) and Special Auxiliaries (locally recurrent characteristics). This allows it to be a truly multidimensional scheme. | |
| Usage | Used especially in specialist libraries and is used in 125 countries (over 100,000 libraries), particularly in Europe and Latin America. Its notation is independent of any particular language or script and has been translated into about 39 languages. | |
| Weaknesses | Its reliance on the DDC base has always been criticized. It may have issues with conflicting functions of some notational devices. |
III. Colon Classification (CC)
The Colon Classification (CC) was devised by Dr. S. R. Ranganathan (1892–1972), with the first edition published in 1933. CC represents the pinnacle of facet analysis theory and is considered the first comprehensive Analytico-Synthetic scheme.
| Feature | Description | Source Details |
|---|---|---|
| Type | CC is a Freely Faceted Classification, guided by Ranganathan’s postulates and principles. The first three editions (1931-1950) were rigidly-faceted. | |
| Structure | CC starts with a set of Main Classes, which are the traditional subjects (disciplines). It recognizes 27 divisions. These main classes are arranged in the order of their evolution as academic studies. | |
| Basis of Order | Classification is based on Facet Analysis and the Five Fundamental Categories (FCs): PMEST (Personality [P], Matter [M], Energy [E], Space [S], and Time [T]). Facets are attached to a basic class in the order of P M E S T (decreasing concreteness). | |
| Notation | Uses a highly mixed notation of Indo-Arabic numerals, Roman capital and small alphabets, punctuation marks (like colon, semi-colon, comma, inverted comma, etc.), and mathematical symbols. The colon (:) links components, giving the scheme its name. | |
| Synthesis/Flexibility | CC is the first example of an Analytico-synthetic scheme in the complete sense. It does not enumerate compound or complex subjects readymade; instead, class numbers are synthesized according to specified rules. This makes its resilience virtually infinite. | |
| Notation Expressiveness | The notation is rigorously hierarchical, extremely hospitable, and highly expressive, depicting facets and categories transparently. | |
| Weaknesses | Has little institutional support compared to DDC and LC. Its complex mixed notation is a barrier to its widespread use and popularity. The complexity was often noted as making notations exceedingly lengthy and confusing. | |
| Components | A CC call number consists of a class number and a book number. |