# Difference between Waterfall Model and RAD Model

Software & CodingSoftware TestingTesting Tools

## Waterfall Model

Waterfall model is the classical model of software development where each phase of software development is completed in a linear fashion. Once one phase is over then next phase starts and in the end the software development is marked completed. Waterfall model works for smaller projects and has one single cycle of development. Following are the phases:

Requirement Analysis -> Designing -> Implementation
-> Testing -> Deployment -> Maintenance

RAD Model or Rapid Development Model is also known as incremental model of software development. It allows changes in any stage which was very costly in case of waterfall model. It has multiple cycles and each cycle delivers a version of a software and after each cycle, new features are added and software is enhanced.

Following are some of the important differences between Waterfall Model and RAD Model.

Sr. No.KeyWaterfall ModelRAD Model
1NameWaterfall model is also named as Classical or Traditional Model.RAD Model, Rapid Development Model is also named as Iterative Model.
2RiskWaterfall model is a high risk model for software development.RAD model is a low risk model for software development.
3Team SizeWaterfall model requires large team to start software development.In RAD model, team size can be increased or decreased as the development progresses.
4ChangesAny changes to be done should in the earlier phases of development otherwise, it is very costly to fix.Changes can be done in any phase.
5Product DeliveryWater fall model delivers product in the end of the software development cycle.RAD model gives earlier deliveries and seeks feedback to update the software as needed.
6Waiting TimeA running or ready software is available at the end stage of development.A running or ready software is avaiable as soon as first iteration is complete.
Published on 15-Apr-2020 06:38:01