forward declarations
<p>Why do I need to use forward declarations for a class when I am already including the relevant header file? It has fixed my problem but confused me!</p>

<p>essentially class A needs to know about class B and visa-versa. I was getting the error "sytax error - identifier" before I included the forward declarations. I was under the impression including a header file essentially meant you WERE declaring the other class where you put #include.</p>
