Multipurpose software for 2D drafting and 3D solid modeling.
http://www.designcad.com/
FastCAD and EasyCAD
Precision 2D CAD programs.
http://www.fastcad.com/
Computer Aided Design
Computer software and (sometimes) hardware used to design things. A CAD system might be as simple as a computerized drafting tool or as complex as a parametric mechanical constraint system, a routing and layout software for integrated electronic circuits, or an architectural program that knows about the physical and spatial properties of constructive elements in a building.