CAD stands for Computer Aided Design or Computer Aided Drafting. CAD was developed in the early 60s. Today it is the premier way to design, develop and optimized products. People use CAD every day to design virtually every product you see. Generally, designers use CAD to design a product, and then produce prints to manufacture that product. A print is a picture of a part or assembly that is very exact. It includes the dimensions and a parts list used to manufacture a product.
CAD is the use of computer based software packages that assist engineers, architects and other design professionals in their designs. CAD is the part of the main designing process and involves both software and sometimes hardware. Current software packages range from 2D vector based drafting systems to 3D solid and surface modelers.

Computer Aided Drafting software packages can generally be broken into two groups. The groups are 2-D drafting packages or 3-D drafting packages. Most all software packages are moving to 3-D design. 3-D design is really the next generation of CAD. Utilizing 3-D design, engineers can make a model of their product. They can then look over this model for any apparent defects before it is ever made.

CAD is used to design, develop and optimize products. CAD is mainly used for the engineering of models and/or drawings of components. It is also used throughout the engineering process from concept to design of products. These products can be used by end consumers or used in other products. For example, you can design a bolt in CAD, and then use it in a Sub-Assembly in a planetary, which is a part of an earth-moving machine. CAD is also used in the design of tools and machinery. Finally, it is used in the design of all types of buildings from sheds to shopping malls.