In software engineering, the first software development model is Waterfall model.
In the 1970, Winston Royce proposed the model for software development , the model is called the waterfall model.
Waterfall model is also called Linear-sequential life cycle model because this model specifies the software development process in a linear sequence manner.
In the waterfall model, the output of the previous phase will be the input to the next phase in the software development life cycle.
Each phase has contains various different tasks and different activity to complete the process.
In this model, we cannot go back to the previous phase to alter any thing if we come to the next phase.
Overlapping is not done with the phases/stages of software development life cycle.
Advantages of waterfall model :
It is easy to use and understand.
No overlapping between the phases.
This model is suitable for small projects.
It is a linear sequence model. It works in a flow step by step
High visibility because output of each phase is generated for the next phase
It provides more flexibility.
This model provides better documentation for the employees.
Low cost.
It is easy to maintain.
Disadvantages of waterfall model :
This model does not work well for large projects.
We cannot go back at previous phase to change anything or any requirement.
No changes can be made in the project.
It can take a long time to complete the project.
High visibility because output of each phase is generated for the next phase
If customer does not satisfied with the project then it is hard to change the requirements.
