Agile and Waterfall represent drastically different approaches to software development -- Agile embraces change while Waterfall prioritizes rigidity.

Waterfall is the older of the two, with roots that date back to the 1950s in infrastructure, engineering and construction. In contrast, the Agile Manifesto, which describes the Agile values and ...

The model’s inherently inflexible and non-iterative form make it worthy of note, but unpopular for most modern software engineering application development environments.