What is Rapid Prototyping ?

It is the creation of reality model, layer by layer,by accepting CAD file as input. The part building may be with Deposition process or by Solidification process layer by layer. The Conversion of CAD data to a prototype model is done by a Rapid Prototyping machine.

Rapid prototyping technique is one among the manufacturing activities that leads in reduction of product development time
A process that automatically creates a physical prototype from a 3D CAD-model in a short period of time by using layer manufacturing method

Why RP ?

Prototype manufacture is very time consuming process and consumes more manpower.
The long cycle time and the high cost of this process limit the number of design alternatives that could be evaluated
Traditional methods of prototyping include modeling with clay or plaster-of-Paris, wood and soft metals or plastics. Complex components are often made in several parts and glued or welded or assembled together

If it is required to build a physical prototype for a critical component, it may be necessary to design and procure tooling, machinery etc., resulting in a long lead-time.
To eliminate above problems an alternative process that would directly give the physical prototype from the CAD model without going through the various manufacturing steps is required.