Ok, I've heard in a lot of places to avoid using too many if's, because they're slow. But I heard somewhere (on this board, once or twice upon a time), that whether or not it's slow depends on what conditions you're testing. So I was wondering, what conditions are slow and what aren't?
i.e.
is this slow:
bool x = false;
if(x)
...

And,

is #1 slower than #2:
#1 -> if(a <= b)
...
#2 -> if(a < b)
...

I'm just sort of confused about what it is that's slow, and I want to clear that up...