is there a difference between selection ( . ) operator and -> ?

Answer 1

-> is used for pointers for returning ,while . is used for connecting...

Answer 2

-> is used for class pointers such as:
MyClass * myObjPtr;
and to use its members or variables you call them with the arrow operator like this:
myObjPtr->DoSomething ();
syntactically, both pretty much are the same, just a few extra characters.