Summary -

In this topic, we described about the below sections -

What is Agile Model?

Agile is a software development methodology where the process involves a collaborative and continuous method of product increment ensuring high quality of the product and process.

What is Waterfall Model?

Waterfall model is a Linear sequential model in which the development process would be sequential. In this model, the next phase of development starts only when the current phase is completely developed. It will not be possible to revert back to previous phase in order to do any kind of changes.

Let us now see the differences between the Agile and Waterfall models.

Agile Vs Waterfall

Differences -

Agile Model Waterfall Model
The Project life cycle in Agile model is divided into sprints. In Waterfall model, the SDLC is divided into different phases.
Agile works on an incremental approach. Waterfall model works on a sequential approach.
Agile method is flexible. Waterfall model is rigid as its structured and sequential.
Agile is a collection of multiple mini projects. In Waterfall model, the entire project is considered as a single project.
In an Agile project, requirement changes are dynamic. Changes are allowed even if the planning phase is completed. In Waterfall model, requirements changes cannot be done once the project development starts.
Agile methodology is an iterative model. So, in each iteration, all the phases such as planning, development, testing etc will be done in every iteration. In sequential Waterfall model, all the project development phases will be completed only once and final.
Test plan will be reviewed after each sprint because there would be different requirements to be covered in each iteration. Depending on that, the test plan may have to be changed. Test plan rarely comes into picture in the testing phase.
In the Agile model, requirements keep changing frequently as per the customer's needs. In waterfall model, the requirements would get freeze at a stage. There will not be any scope of changing the requirements again and again.
In Agile methodology, Testing will be done in parallel with the development. In Waterfall model, Testing phase starts once the development is completely done and the build is completely ready for test.
Agile works on a product mindset wherein the Waterfall model totally works with a project
product development is transparent to the end user and the end user can propose changes as per their requirement and need. mindset. Its focus is always on the completion of the project.
Agile model goes good with Time and money projects rather than Fixed bid projects. Waterfall model completely goes with fixed bid projects and low risky.
Product owner prepares requirements on a daily basis as per the end user needs during the project. Business Analyst prepares requirements in the Analysis phase itself for the project.
Test team can take part in the requirements change without any issue. Test team cannot change any requirements.
Detailed description of the project can be changed/altered anytime during the SDLC process. Detailed description of the project must be completed in order to implement the Waterfall model.
Agile supports the Test Data Driven Approach. Waterfall model does not support Test Driven approach.
Agile method is customer centric. It supports Sequential funding model.
Agile model given transparency on the progress of the work. Customer would not be able to see the product until it is delivered completely.
The main focus would be on Business value. The focus is on disciplined and systematic approach.
Immediate user feedback would help to lower the risk of failure. User feedback cannot be given until the product is completely developed and delivered.
Focuses on continuous improvement. Continuous improvement cannot be implemented in this model as the waterfall model would take more time for completely developing the product and delivering.
Forward and Backward implementing would be easy. Iterative way of implementation.
Documentation is not so important. Process and results would be well documented.