The subject “Computer-Aided Design” is basically meant for the application of computers to make engineering design and drawings more accurate, less time consuming, and increase productivity of designers involved in Civil, Mechanical, Architectural, Automobile engineering fields. The content of this book basically covers the topics related to fundamentals of Computer-Aided Design using software such as AutoCAD and SolidWorks 3D modeling. It consists of understanding and practicing basic 3D commands of both parametric and non-parametric environments of SolidWorks and AutoCAD respectively. The basics of graphic transformation with illustrative examples and exercises are also included as fundamental information of computer graphics. The information regarding various basic hardware devices is also included in order to highlight the CAD workstation requirements. The contents also highlight the step-by-step procedures to follow the command instructions to run the software on a more practical basis with illustrative examples and a case study. Overall I can conclude that all students pursuing their diploma programs and degree programs and practitioners involved in mechanical parts modeling, assembly modeling, engineering drawing, drafting, and designing can get benefited from the contents and sub-contents of the book.