Definition
The Waterfall model is a sequential project management approach where progress flows steadily downwards through distinct phases. Each phase must be fully completed before the next one begins, creating a linear and structured development process. This methodology breaks down projects into manageable stages like requirements gathering, design, implementation, testing, deployment, and maintenance. It matters on the job because its rigidity helps ensure thorough documentation and clear deliverables at each step, reducing ambiguity. For instance, building a simple, well defined software application might follow a Waterfall approach from initial concept to final release. Unlike iterative models that allow for frequent feedback and revisions, Waterfall requires all requirements to be finalized upfront. This concept is frequently tested on PMP and CAPM certification exams.