Rapidly developing an initial software implementation from very abstract specifications and modifying this according to your appraisal.
The Evolutionary Life Cycle Model also supports the development of a system in increments. However, it differs from the Incremental Model in that the requirements are developed as part of each increment. This model requires that the project scope activity be thorough, resulting in a solid understanding of the high-level functions to be implemented.
Each of those high-level functions is then allocated to one of the increments for further definition and implementation.
In the Evolutionary Model, the initial increment typically includes only those requirements that address the core requirements and their functions with subsequent increments introducing additional functions. Each increment then follows either the Traditional Waterfall Model or the Modified Waterfall Model for the Define, Build, Test and, optionally, Deploy activities. As with the Incremental Model, not every increment need be deployed into the production environment.