CAD stands for Computer-Aided Design. It is the use of computer software to create, modify, analyze, and optimize designs, often for engineering, architectural, or product design applications. CAD software allows designers and engineers to create precise and detailed 2D or 3D models, which can be viewed, manipulated, and tested on a computer. CAD has revolutionized the design process, allowing for faster and more accurate design iterations, as well as improved collaboration between designers, engineers, and other stakeholders.