This textbook has been written according to the new revised syllabus of West Bengal University of Technology for the first year (first semester) BTech. students of all branches and BArch. students. It consists of thirteen chapters and two appendices. This book can also be treated as a supplementary book of BE/BTech./BArch. students of other universities. This book contains various types of problems along with worked out model problems which are essential to the Engineering/Technological and Architecture students. Multiple choice questions with answers have been provided in this textbook which will be helpful for GATE and other competitive examinations.