What Is Waterfall?

Waterfall methodology follows a sequential, linear process and is the most popular version of the systems development life cycle (SDLC) for software engineering and IT projects. It is sometimes planned using a Gantt chart, a type of bar chart that shows the start and end dates for each task. Once one of the eight stages are complete, the development team moves onto the next step. The team can’t go back to a previous stage without starting the whole process from the beginning. And, before the team can move to the next stage, requirements may need to be reviewed and approved by the customer.

The Waterfall model originated in the manufacturing and construction industries, both highly structured environment where changes can be too expensive or sometimes impossible. The first formal description of Waterfall is attributed to Winston W. Royce in a 1970 article where he described a flawed software model.