It is also called successive versions model or incremental model. At first, a simple working model is built. Subsequently it undergoes functional improvements & we keep on adding new functions till the desired system is built.
- The incremental model combines elements of linear and parallel process flows
- The incremental model applies linear sequences in a staggered fashion as calendar time progresses
- Each linear sequence produces deliverable “increments” of the software
For example, word-processing software developed using the incremental paradigm might deliver basic file management, editing, and document production functions in the first increment; more sophisticated editing and document production capabilities in the second increment; spelling and grammar checking in the third increment; and advanced page layout capability in the fourth
Applications:
- Large projects where you can easily find modules for incremental implementation. Often used when the customer wants to start using the core features rather than waiting for the full software.
- Also used in object oriented software development because the system can be easily portioned into units in terms of objects.
Advantages:
- User gets a chance to experiment partially developed system
- Reduce the error because the core modules get tested thoroughly.
Disadvantages:
- It is difficult to divide the problem into several versions that would be acceptable to the customer which can be incrementally implemented & delivered.