What are different types of parameters? How can you distinguish between different kinds of parameters?

The different types of parameters are

a)      Formal Parameters:  It is defined during the definition of subroutine with the ‘FORM’ statement

b)      Actual Parameters:  It is specified during the call of a subroutine with the ‘PERFORM’ statement

You can distinguish different kind of parameters by their functionality.  Input parameters are used to pass data to subroutines, while output parameters are used to pass data from subroutines.