Civil engineering is a professional engineering discipline that deals with the design, construction, and maintenance of the physical and naturally built environment, including works like roads, bridges, canals, dams, and buildings.Mechanical engineering is the discipline that applies engineering, physics, and materials science principles to design, analyze, manufacture, and maintain mechanical systems. It is one of the oldest and broadest of the engineering disciplines.Objective of our book to impart basic knowledge on Civil and Mechanical Engineering.To explain the materials used for the construction of civilized structures.To make the understand the fundamentals of construction of structure.To explain the component of power plant units and detailed explanation to IC engines their working principles.To explain the R & AC system.