Waterfall model

From Wikipedia, the free encyclopedia

The waterfall model is a breakdown of project activities into linear sequential phases, meaning they are passed down onto each other, where each phase depends on the deliverables of the previous one and corresponds to a specialization of tasks.[1] The approach is typical for certain areas of engineering design. In software development,[1] it tends to be among the less iterative and flexible approaches, as progress flows in largely one direction ("downwards" like a waterfall) through the phases of conception, initiation, analysis, design, construction, testing, deployment and maintenance.[2][better source needed] The waterfall model is the earliest SDLC approach that was used in software development.[citation needed]

The waterfall development model originated in the manufacturing and construction industries,[citation needed] where the highly structured physical environments meant that design changes became prohibitively expensive much sooner in the development process. [citation needed] When first adopted for software development, there were no recognized alternatives for knowledge-based creative work.[3][better source needed]