I am indebted to my parents for their blessings. Their good wishes and unstinted support bolstered my confidence while embarking on this venture. This book could hardly have been possible but for the endless support of Mr. Ankush and I thank him for his cooperation and encouragement all through.I am thankful to my friends and to my guide Ms. Asma Tuteja. My thanks are due to the members of Sarah Lynch Acquisition Editor LAP LAMBERT Academic Publications, Germany for their interest in the manuscript and their involvement in bringing the book to this final form.