Waterfall model

Waterfall model is one of the simplest model used in software development process. This is suitable to well defined systems and centers around planed processes. Waterfall model also known as the liner model because it is an execution of sequential activities or processes. One process start only after completion of the immediate previous process. Each phase produces a detailed document for the next phase. Team members assigned for the each level and they are responsible for the accurate self completion of the assigned phase.

This model is generally time consuming and requires a good documentation and debugging (error handling) could becomes difficult for large systems. Because an error could be flows in to many above levels in the system testing phase.