In the pass by reference we are using the pointer that is
here, we are passing only address where value is stored. but
in the case pass by value we are using ordinary variable
that is pass the value itself. here the value cannot be
changed in calling function and returning back to called
function but this is possible in call by reference

in pass by value only the actual value of a variable is 
copied to a formal parameter & it doesn't effects the 
actual value when any operations r done on it
where
 in pass by refference we r sending address of variables it 
gives exact results but any oprations done on it may effect 
actual values

pass by value :passing the varibles directly into function 
augments

pass by reference:
passing the address of the pointer varible

In pass by value we can pass value through the arguments

In pass reference with the help of operation