Waterfall Model
The Waterfall Model is a linear, sequential software development methodology where progress flows steadily downward through distinct phases like requirements, design, implementation, testing, and maintenance. Each phase must be completed before the next begins, with minimal overlap or iteration, making it highly structured and documentation-heavy. It originated in manufacturing and construction industries and was adapted for software development in the 1970s.
Developers should learn and use the Waterfall Model for projects with well-defined, stable requirements, such as government contracts, safety-critical systems (e.g., medical devices), or when regulatory compliance demands extensive documentation. It is suitable when changes are costly or unlikely, as its rigid structure ensures thorough planning and clear milestones, reducing ambiguity and risk in predictable environments.