Exception handling

Whenever there is an error in your code then we need to handle the error in a proper way otherwise the system generated error message will be thrown to the user.
Moreover the end user will not understand the error messages from the application.
If you're not handled the error,the application may crash.

For more details, please read the following articles.
http://www.c-sharpcorner.com/UploadFile/puranindia/ExceptionHandlingCsharp07082009014725AM/ExceptionHandlingCsharp.aspx
http://www.c-sharpcorner.com/UploadFile/susanabraham/CustomExceptionHandling06022005011154AM/CustomExceptionHandling.aspx
http://www.c-sharpcorner.com/UploadFile/rekhasingh1610/208192009021309AM/2.aspx