Binary Tree Recursive Function

[MasterGberry]

So this is a topic asking for a good explanation if possible rather than code fixes :)

So I had this code which originally took two parameters of pointer type and then I changed it to pointer references (or reference pointers?) (tell me which one it is) and it started to work. Now this kind of makes sense to me, as before I was just pointing a memory address but not changing how the pointer acts with that memory address...and now that i am passing a reference of the pointer itself? In which case I am directly changing the pointer? Do I have this right?

Please Note: This function is not yet complete, and only the first if statement and first two else if's work.

void BinaryHash::insertNode(node *&tree, node *&n)
{
	if (tree == NULL)
		tree = n;
	else if (tree->value > n->value && tree->leftHTChild == NULL)
		this->insertNode(tree->leftChild, n);
	else if (tree->value < n->value && tree->rightHTChild == NULL)
		this->insertNode(tree->rightChild, n);
	else if (tree->value > n->value && tree->leftChild == NULL)
		tree->leftHTChild->insert(n->value);
	else
		tree->rightHTChild->insert(n->value);
}