As soon as the AUT is actually ready for Testing, the practical period of testing cycle starts in which testers really execute the test cases on AUT. Keep in mind that here the tests cycle is actually discussed regardless of Testing Levels (Unit, Module, Integration, System and User Acceptance) and Testing Environments (Dev, QA, Client’s Replica, Live).

a. Smoke Testing: The very first testing cycle that is certainly broad and shallow in approach. The purpose of smoke testing is to verify that there are no crashes in the application and it is suitable for further testing.

b. Sanity Testing: The second testing cycle that is certainly narrow and deep in its approach. Its objective is to authenticate that a specific module is working properly and is suitable for complete testing.

Tip: Usually there is not ample amount of time available to run these two cycles individually. So, a mixture of both these cycles is adopted in practical.

c. Functional Testing: The proper and full fledged testing of application is actually performed in this cycle. The primary emphasis of this activity is usually to verify the business logic of the application.

d. Regression Testing: This is the final cycle of testing in which the bug-fixes and/or improvements are verified. Moreover, regression testing also makes you don't have malfunctioning in other areas of AUT due to fixes and changes.

Bugs are logged in every testing cycle. There is no distinctive border line among the testing cycles. For example, in Regression the Functionality is also verified and it may also require smoke, sanity or their merger first.