What does this sign do?

I've looked in some gamecode and I don't understand what this sign does: test->test2. What does the '->' sign do exactly?

It's the indirect-access operator. For example:

Code:

---

struct mystruct {
    int y;
    int x;
};

mystruct str;
mystruct *ptr = &str; // Get pointer to str

int num = ptr->y;
int snd = str.x;

---

So, it's basically: pointer->member, and is equivalent to (*ptr).member. It's to make it more readable, because rather than:
(*((*ptr).ptrmember)).member you can use ptr->ptrmember->member.