The return line of a function is a variable, a function call or an expression that results in a variable of the return type of the function. This value is returned from the function and is used in an assignment, in an expression or ignored by the calling function.
The return line can only be on the last line of a function. If the function has a return type (i.e. not void) then the function must have a return line. If the function does not have a return type (i.e. the return type is void) then the function cannot have a return line.