Notation: Need, Functions, Characteristics

The sources provide extensive information on the Notation used in library classification schemes, covering its need, functions, and various characteristics (qualities).

I. Need and Purpose of Notation

Notation is essential in library classification primarily because it provides the mechanism necessary to translate the intellectual arrangement of subjects (Idea Plane) into a predictable and manageable physical order.

The need for notation arises from the deficiencies of natural language and the requirements of mechanized arrangement:

1. Mechanized Arrangement and Order: Notation is required to mechanize the arrangement of documents on the shelves and their entries in catalogues and other bibliographical tools. If a suitable arrangement is determined, notation ensures that this sequence is permanent and does not have to be re-determined when documents are returned or when new documents are interpolated.
2. Unsuitability of Natural Language: The names of subjects in natural language are unstable, not unique (due to synonyms and homonyms), and differ across languages, leading to unhelpful alphabetical scattering. Notation, being an artificial language of ordinal numbers, resolves these terminological problems.
3. Translating Subject Content: Notation translates the specific subject of the document into the artificial language of the classification scheme's ordinal numbers. This translation enables the classification of subjects.
4. Individualization (Call Number): Notation provides the class number which, when combined with the book number and collection number, forms the Call Number, which uniquely identifies and locates a single document copy in the library.
5. Filing and Indexing: Notation makes the arrangement of entries in the catalogue possible, whether in a classified sequence or through the Alphabetical Index.

II. Functions of Notation

Notation performs several vital functions, primarily ensuring mechanical maintenance of subject sequence and aiding organization and retrieval:

1. Maintaining Sequence (Ordering Device): The vital function of notation is to mechanically maintain the sequence of subjects by assigning each term a symbol with an agreed ordinal value. This applies to arrangement on shelves (shelf order) and arrangement of entries in a catalogue or bibliography.
2. Showing Sequence and Subordination: Notation shows the classified sequence of subjects and the subordination and co-ordination of the subject symbolized. This function is related to the quality of expressiveness.
3. Reference and Location: Notation assists in the grinding of a library (location of documents) and allows mechanical reference from any catalogue entry to the material on the shelves.
4. Enabling Synthesis (Number Building): The use of synthesis (number building) by notation facilitates enormous economy in the construction and physical size of the schedule.
5. Mnemonics: Notation assists both librarians and readers by possessing mnemonic qualities that help in remembering the sequence of divisions within a class.
6. Alphabetical Indexing: It makes the alphabetical subject index possible by providing a precise location symbol (class number) alongside the term (e.g., algebra 512).
7. Administrative Uses: Notation is used for charging and discharging of documents and is written on various parts of documents and cards.

III. Characteristics (Qualities) of Notation

For notation to perform its functions effectively, it must possess specific qualities or characteristics. Ranganathan suggested several qualities, some mandatory and others desirable:

A. Mandatory/Structural Qualities

1. Complementary Nature: The nature of notation should be complementary; it is not primary. The classification (Idea Plane) should determine the notation, not vice versa.
2. Avoidance of Synonyms: The notation must avoid synonymous class numbers, meaning each subject should be represented by only one class number.
3. Avoidance of Homonyms (Uniqueness): The notation must avoid homonymous class numbers, meaning one class number should not denote more than one specific subject. Each class number of a specific subject should be unique.
4. Expressiveness (Hierarchical/Structural): An expressive notation reflects the structure of the scheme by showing subordination and co-ordination. It helps the user find their way up in a systematic order. However, an expressive notation often ceases to be brief because each step in division requires an additional digit.
5. Hospitality: The system should have the capacity to accommodate new classes. This is referred to as Hospitality in Array (for coordinate classes) and Hospitality in Chain (for subordinate classes).

B. Desirable/Optional Qualities

1. Brevity: Brevity is a desirable quality as it aids staff in recording numbers and users in remembering them. Due to the growing complexity of subjects, notations tend to be longer; however, brevity is often achieved through the judicious use of synthetic features.
2. Universal Usability: The symbols should be universally used because class numbers are used by people drawn from different backgrounds. The use of decimal notation (as in UDC) has made it a truly international classification.
3. Block Formation: Long class numbers should be divided into convenient blocks, as the optimum number of digits that can be comfortably retained in one instance is generally three, with a maximum of six.
4. Synthesis: The notation should possess the quality of synthesis (number building) by allowing components to be taken from different parts of the schedule. This is especially pronounced in faceted schemes.
5. Pronouncibility: This is an optional quality, where notation can be arranged to be suitable for direct pronunciation or easier memorization.
6. Mnemonics: The notation should facilitate the use of different types of mnemonic devices (alphabetical, scheduled, systematic, seminal) to aid memory.

C. Species and Types of Notation

Notation uses various species of digits, including Arabic numerals, Roman letters, punctuation marks, and mathematical symbols. Based on the mixture of these species, notation is classified:

• Pure Notation: Uses only one species of digits (e.g., DDC's reliance on Arabic numerals, though it is now often described as mixed due to auxiliary tables).
• Mixed Notation: Uses two or more species of digits in a class number (e.g., CC, UDC, LC). This is adopted to achieve greater capacity and expressiveness.
• Faceted Notation (Multipartite): The number consists of blocks of digits (facets) connected by meaningful indicator digits (analogous to punctuation marks) which show the interrelation between component ideas. CC and UDC utilize faceted notation.
• Non-Faceted Notation (Unipartite): Also called non-structural or non-hierarchical, this notation consists of digits written closely to form one block. Enumerative schemes like LC are often characterized by this type.