This is the process of testing the pure business process/rule of the application
This is the process of finding out defects based on
1. Concurrent User testing
2. Performance testing
3. adhoc testing to find out any database error
4. stress testing
This question has been asked many, many times in the past. I suggest you familiarize yourself with the search feature in the upper right hand corner, and use it prior to posting a question on the forum.
Success is the ability to go from one failure to another with no loss of enthusiasm.
~ Winston Churchill ~