So, for now, I'm just going to assume that we're working in the two-player zero-sum setting and it does extend in some cases to other situations as well. So, our goal is to find an approximate Nash equilibrium. We're going to measure performance in terms of exploitability. You can think of it as, distance from a Nash equilibrium, it's how well we would do against a worst-case adversary relative to if we had played a Nash equilibrium instead. So, how exploitable we are? I would argue that exploitability is actually extremely important and has