Basically retest the application and ensure that the applications are working as per the requirements even though there is the change made in another part of the applications.
Once the application had been implemented in the production and the new features had requested by the client and the developers had develop it, Regression testing is done on the applications before it is put in to the applications to ensure that the new features apply on the applications couldn’t affect the existing feature already have in the application.
At the time of creating the new products in each stage of developing the new product new features are getting added and however with the help of regression testing we can able to check that the new features doesn’t affect the existing features in the application.
Each and every time existing test cases which is developed earlier is tested against the applications.
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