This textbook is specifically designed for the students of B.E. / B.Tech., B. Arch., Diploma in Engineering, and those preparing for U.P.S.C. Examinations (Engineering and Civil Services), AMIE, GATE, and various other engineering competitive examinations. This book is written in a simple and lucid language so that students can understand the subject even by self-study. This book is intended to be useful also to the faculty members teaching the subject. It will serve as a valuable source of information and reference book for post-graduate students, interview preparations, and industry professionals alike.