This is another very old model for project management that can be considered as a combination of the Waterfall and iteration models. In the Spiral model, a list of requirements is identified for each iteration, which is known as a spiral. The output of every spiral is a small prototype of the project. The client can review this prototype and provide feedback. Similarly, requirements are identified for the next spiral. This process is followed until the project is complete and ready for delivery. As we can see in the following Spiral model diagram, a small prototype is developed in each spiral:
There are four phases in ...
