Comparison between Prototype & Spiral Model:-

1.Spiral model is called a meta model.Spiral model is made with the features of Prototype model and Waterfall model.

2.Spiral model takes special care about Risk Analysis. Whereas it is not given importance in Prototype model.

3.Prototype model is suitable when the requirement of the client is not clear and it is supposed to be changed. It doesn't cover any risk management. While Spiral model is an enhancement of the prototyping model with so many extra features.Spiral model has the facility of risk analysis and many more.

4.In spiral model customer interaction continuous to move together. in other hand prototype model customer interaction needs till the prototype is approved.

5.In spiral model no cost effective quality improvement possible but in prototype model cost effective quality improvement is possible.

6.Quality improvements may increase costs excessively but in Prototype model Quality improvements not increase any costs.

7.New methods might cause existing staff to leave but in Prototype model new methods didn't cause existing staff.

1. I never saw the spiral model used in practice, and prototyping used in practice.