These arguments are referred to as formal arguments . Formal arguments must be variable names and cannot be expressions and constants. It has two formal arguments n and Answer . The following is a subroutine called TestSomething . It takes four formal arguments a , b , c , and Error .
Subroutines can be internal to a program or a module.
Unlike functions, the name of a subroutine is not a special name to which you can save a result. Subroutine's name is simply a name for identification purpose and you cannot use it in any statement except the CALL statement. A subroutine receives its input values from its formal arguments, does computations, and saves the results in some of its formal arguments.