This book is the final publication of the term paper with the same title submitted in the Department of Commerce, Delhi School of Economics, University of Delhi. It has been published now due to instability of my life's journey and the detour it had taken till date. The topic was chosen and conceptualized due to intense desire to understand human being and their behavior and communication abilities and techniques. This intense desire was the direct result of the unfolding of my life's events. Because of all this, I didn't try to change it much to keep its originality and essence intact.