The Definition of a Prototype according to the Oxford Dictionary: The original thing or person in relation to any copy, imitation, representation, later specimen or improved form.

The Need for a Prototype: It is very difficult, and in many instances impossible, to produce an article that will serve the purpose of use without making modifications to the original shape or general design. There are many examples of design failure that have been the cause of serious injury and costly litigation.

Rapid Prototyping concentrates the mind on getting the product - Right First Time

Other uses for RP modelling:

• Discussion piece.
• Design and fit.
• Assembly capabilities.
• Suitability of mechanical properties.
• Manufacturing process capabilities (forging, casting, pressing, fabrication etc.)

In the context of casting production, or indeed any component and method of manufacture, the design, manufacture and proving before acceptance can be very costly in terms of time, money and frustration. The following chart indicates those stages that are normally encountered in the traditional method of producing a prototype casting.