Constraints:

This unit calls for a comprehensive and thorough treatment to cover the various aspects of history and development of library catalogue codes. However, such a thorough treatment is not easy to attempt. There are constraints and limitations. The seemingly simple rules in the catalogue codes, in reality, are not simple. They have been formulated empirically. In the early stages and for quite long time, cataloguing activities in libraries were not aided by any rules. Catalogues were compiled for individual libraries applying the ingenuity and common sense possessed by their compilers. When the collections grew and became formidable, some guidelines became necessary so that the work by the successive generations of cataloguers would conform with that of their predecessors. The emergence of the printed catalogue in the 17th century established the need for rules so as to ensure consistency in continuation and updation, cumulation or revision of the catalogue. Thus, rules for the compilation of (printed) catalogues were drawn, based on past experiences. The idea of cooperation in cataloguing promoted from the beginning of the 19th century sought uniformity as an additional virtue. One time cataloguing to eliminate wasteful duplication of cataloguing efforts in the individual libraries became an ideal. The questions of what rules to be made and on what basis should they be made became the concern. Answers were sought in the conventional wisdom, through theoretical postulation of principles, and by formulation of objectives and functions in tune with changes and developments taking place in the bibliographic world. 

The rules, which came up largely through the empirical path and progressed on the route to universalisation and internationalisation have an intellectual content and a unity of thought as well. What is appropriate, therefore, in the study of their history and development is elicitation of the intellectual content, clarification of the cataloguing concerns of different periods, and appreciation of the problems faced and the solutions found, the gradual maturation and crystallization of. ideas obtained as also the logical principles and postulates underlying the codifications of rules. Mere chronological accounting of the history and chronology of the codes is not of great help.  

The fact that the history of cataloguing rules has yet to be systematically written is true to a great extent. Barring a few historical accounts here and there of catalogues and cataloguing, comprehensive, cohesive and thoroughly written accounts of the history and development of library catalogue codes do not exist. For instance the history of catalogues in India and many other parts of the world is yet to be attempted. This lacuna is a major constraint. Even for the limited purpose of this unit any attempt at presenting a critical summary and piecing together of the essential parts is rendered difficult. Space is another constraint. It cannot also be treated in great elaboration disregarding the proportion in relation to other units.