This is the first ever book in sociology that tries to give quantitative significance values to some of the most significant sociological concepts, that appear to form the core of the discipline. It makes an in-depth study of about one hundred main concepts of sociology, identified through a literature survey of about 87 textbooks. These main concepts appear to be the core aspects of study, teaching and research in sociology. The concepts have then been grouped under some major sections. A detailed classification schedule for the term Concept has been suggested along with a bibliographic survey of the literature on concepts. Taking into consideration about 500 aspects of sociology, a detailed classification schedule has been suggested. The schedule for sociology in the Dewey Decimal Classification scheme has been examined with regard to filiatory structure, terminology used cateorization, and representation of main sociological concepts. The last section of the book, arranges about 5000 terms used in sociology, also show their availability in eight dictionaries of sociology, as well as the class number and the terms used in some library classification schemes. The book is of interest both for sociologists and the Library Science professionals.