Prototype model

Prototype model
In this model, a prototype (an early approximation of a final system or product) is built, tested, and then reworked as necessary until an acceptable prototype is

finally achieved from which the complete system or product can now be developed.
Prototype paradigm begins with requirements gathering. Developer and customer meet and define the overall objectives for the software, identify whatever

requirements are known, and outline areas where further definition is mandatory.
A quick design occurs which leads to the construction of prototype.
The prototype is evaluated by the customer/user and used to refine the requirements for the software to be developed.
Iteration occurs as the prototype is tuned to satisfy the user requirements, while at the same time enabling developer to better understand what needs to be done.

Advantages:

When ever the customer with the requirements then this is the best model to gather the clear requirements.

Drawbacks:
It is not a complete model.
Time consuming model
Prototype has to be build company’s cost
The user may strict to the prototype and limit his requirements