Introduction
Iterative development lies at the heart of how OOA/D is best practiced and is presented in this book. Agile practices such as Agile Modeling are key to applying the UML in an effective way. This chapter introduces these subjects, and the Unified Process as a relatively popular sample iterative method.[View full size image]Iterative and evolutionary development
contrasted with a sequential or "waterfall " lifecycleinvolves early programming and testing of a partial system, in repeating cycles. It also normally assumes development starts before all the requirements are defined in detail; feedback is used to clarify and improve the evolving specifications.