Rajendra, the Tester

Types of Regression Testing:
We have following four types of regression testing techniques.
1) Corrective Regression Testing: Corrective regression testing applies when specifications are unmodified and test cases can be reused.
2) Progressive Regression Testing: Progressive regression testing applies when specifications are modified and new test cases must be designed.
3) The Retest-All Strategy: The retest-all strategy reuses all tests, but this strategy may waste time and resources due to execution of unnecessary tests. When the change to a system is minor, this strategy would be rather wasteful.
4) The Selective Strategy: The selective strategy uses a subset of the existing test cases to reduce the retesting cost. In this strategy, a test unit must be rerun if and only if any of the program entities, e.g. functions, variables etc., it covers have been changed. The challenge is to identify the dependencies between a test case and the program entities it covers.