C.A.D is an abbreviation  for the words computer aided Design or computer aided drafting .The computer is used to input data in the form of lines, curves, dimensions and text into the data base of a program to produce 2 or 3 dimensional (2D or 3D)Designs.  

 

 

2D CAD

 These are  drawings in 2 axes that  produce flat views of a design. The design can be dimensioned. The data can be changed to modify the design at any stage.

 

3D CAD  virtual prototypes

The design produced is in 3D and hence looks like a solid that can be rotated and viewed from different points. Data can be easily changed to modify the design at any stage. The dimensional accuracy of such models allow designers to build their new designs in a life-like environment whilst still at their desk.