Definition of Library Classification:

Having understood the meaning of classification in library science, let us now go through a few well-known definitions of library classification. Library classification has been defined by both the classificationists and the critics, all necessarily underlying its utilitarian aspect. According to Margaret Mann, classification is "the arranging of things according to likeness and unlikeness. It is the sorting and grouping of things, but in addition, classification of books is a knowledge classification with adjustments made necessary by the physical form of books". W.C. Berwick Sayers defines it as the arrangement of books on shelves or description of them in the manner which is most helpful to those who read". Arthur Maltby revises Sayers definition as "the systematic arrangement of books and other material on shelves or of catalogue and index entries in the manner which is most useful to those who read or who seek a definite piece of information". Ranganathan is more elaborate in his definition. We will study his definition, therefore, in detail. According to Ranganathan, "it is the translation of the name of the subject of a book into the preferred artificial language of ordinal numbers, and the individualisation of several books dealing with the same specific subject by means of a further set of ordinal numbers which represent some features of the book other than their thought content". In this definition, we find three important phrases, viz., 

i)  artificial language, 

ii)  ordinal numbers, and 

iii)  specific subject.