Introduction

The work of practical library classification, in essence, is to find an appropriate place for a document in the overall scheme of subjects in a given classification system. It is based on the subject content of the documents, though classification is more than content analysis and coding. Practical classification consists of two phases:

• 1 Subject analysis – the intellectual work of determining the specific subject of the document; and

• 2 the mechanism of assigning the appropriate class number from the schedules for the subject and doing number building, if required.

These two phases can be likened respectively to medical diagnosis and the prescription and dispensing of medicine. Subject analysis is the most important in the process and indeed the very essence of classifying, somewhat independent of the knowledge organization system used. A mistake at this stage will invariably percolate to produce wrong results. Determining the specific subject of a given document is an art which machines cannot do – or at least not yet. It is an intellectual work of the highest order, done by experts in the Idea Plane according to S. R. Ranganathan's theory (Satija, 2014). It sometimes requires intuitive insights which come from a wide acquaintance with knowledge and written literature. Such knowledge constantly improves with reading and experience, though one may never gain perfection in this art. Proficient classifiers know something about almost everything. Indeed, intense specialization in research and rapidly advancing frontiers of knowledge have made this task more daunting, though by no means impossible.

Determining the specific subject

The specific subject of a document may be determined by examining its title, subtitle, blurb, preface and table of contents and scanning through the text, if necessary.

The institutional affiliation of the author, the index, the series and cited references may also provide valuable clues. A classifier may occasionally read published reviews or consult some reference tools to understand the publication under consideration. If all these efforts fail, the last resort is to consult a subject expert.

Title as a subject indicator

The title is the proper name given to a publication. It is supposed to clearly indicate the subject of a nonfiction work. Often it will do so, but not always. Ideally, it will concisely indicate the subject of the document. We categorize titles into three kinds.