Principles of Mechanical Engineering is a comprehensive and systematically structured textbook designed to cater to the needs of undergraduate engineering students. This book offers a well-balanced treatment of both theoretical foundations and practical applications of mechanical engineering principles. Covering a broad spectrum of essential topics— from thermodynamics and fluid mechanics to strength of materials and machine tools. The book is tailored to help students build a strong conceptual base and excel in university examinations as well as competitive technical assessments.