The formal parameter list versus the actual parameter list

The formal parameter list - The formal parameter list is part of the function signature, which in this case looks like this (see Listing 3):

void aFunction(int x,double y)

(The formal parameter list is shown in boldface in the above function signature.)

The actual parameter list - The actual parameter list is part of a function call, which in this case looks like this (see Listing 3):

aFunction(a,b);

(The actual parameter list is highlighted in boldface in the above function call.)