Waterfall Model

Waterfall model is one of SDLC model (Software Development Life Cycle) which helps to develop application in organised way.

In Waterfall model, Application life cycle is devided into following phases:

1. Requirement Gathering
In this phase, We need to gather requirement from the client and create RUD (Requirement Understanding Document) or SRS (Software Requirement specification). We also need to approve those document from Client to move to next phase.

2.Design
In this phase, We need to develop mock-up which will help to client to understand how application will work after development. If there is any change required then client suggest in this phase, so we can save our time in development. After getting approval on design, we need to move to next phase.

3. Implementation
In this phase, we will start implementation. Before going to implement anything, Develop needs to create unit test case document which helps to trace requirement with the SRS or RUD document. Unit testing is part of this phase only.

4. Verification or Testing
In this phase, QA will test the application and check all the requirement is developed as per specification in RUD or SRS. If QA will find any bugs then Developer need to resolve.

5. Deployment
In this phase, We need to deploy application on production machines.

6. Maintenance
In this phase, We need to give support to application on production machines. If any bugs found after deployment then developer needs to solve the bugs.