Sanity Testing and Smoke Testing

What is Sanity Testing and Smoke Testing?

Smoke Testing : Test Scripts are generated in such a way that crucial functional parts of the System are covered. Here Tester is trying to cover major functionalities that are suppose to work fine.Usually before the release of any prodcut Smoke Test is conducted to ensure crucial functionalities are working as they suppose to function. 

Sanity Testing: Sanity Test is  in depth Regression, Test may be conducted at the very low level. Usually script is not written for Sanity Test.

ReTest and Regression Testing

What is  the difference between Retesting and Regression Testing?


ReTesting :  is testing the functionality which is already tested. 
  
eg;- We test "Book Withdrawal Functionality of Library". if  Tester  finds a defect  in the functionality he will raise a defect. Once the developers fixes the issue. Tester is Retesting the same functionality. 


Regression Testing : When any changes occur in the existing system Tester tests the new functionality and  also tests  how the new changes are getting effected with the already existing functionality. 


eg:- If the Withdrawal functionality of the Library system is updated to support withdrawal for outside users. 
Here Tester is testing working of withdrawal functionality of Out Side users and also Testing existing User to validate already existing functionality are working as required.