Hi Srishti Gupta, Please check this article:
Using Try... Catch..., Finally![
^]
Gives you a good insight of exception handling..
It is not mandatory to have a finally block always. But it is advisable. You can dispose all the objects which you don't need. Also it can be used when you need to write some code that needs to be executed irrespective of an exception occurs or not.
Hope it helps.
Regards
Dinesh Kumar.V.