SDLC - Spiral Model

   Spiral model is an model that combines elements of an iterative software development model with a waterfall model.

- In this model, appication is develope and taste in modules and handed over to the client so they can start testing early.

- In spiral model we release a multiple build of application.

- In this model, we develop the application in the stages because sometimes the client gives the requirements in between the process.

- It is suitable when requirements are change frequently 

-  The spiral model is perfect for projects that are large and complex in nature as continuous prototyping and evaluation help in mitigating any risk.