The Default Parameter Passing Mechanism Is

The default parameter passing mechanism is Call by value in a C-language which passes the value of the actual parameter. Whereas call of reference refers to giving the address of the memory location where the actual parameter is stored. The latter method allows the procedure to change the parameter’s value, while the former method ensures that the procedure does not change the value of the parameter. Other more complex ways of passing parameters have been developed, notably called by name in Algol 60, where the actual parameter is re-evaluated each time.