Evolutionary model follows building of the required product in several successive versions.
It is also known as incremental model.
Important points on evolutionary model
In evolutionary development model the requirement is broken down into different functional units.
These functional units can also be referred to as module. These modules can be incrementally built and delivered.
Here at the beginning the core module of the software product is developed.
New functionality is built, added to existing one and released as new version.
Each successive version is capable of performing more functions in comparision to its previous versions.
Release of different version in evolutionary model is shown below:
Each of the version will be released with new added functionality.
Version V2 will have more functionality capability than its previous version V1 but will exhibit less capability in terms of functionality from V3.
As the model seems to be developed in the incremental way so it is termed as incremental model of the development.
Where evolutionary model is suitable to use?
Evolutionary model is suitable for Object oriented software development product. Its because in OOP requirement can be separated in different modules in terms of the objects.
It is also suitable for large products where requirements can be divided into modules.
Every version will get built and delivered to customer who can then use it instead of waiting for the complete system.