In fact, the definition of a derivative uses the notion of a limit. It's a slope around the point as we take the limit of points closer and closer to the point in question. You've seen that many, many, many times over. In this video, we're going to do it in the opposite direction. We're going to use derivatives to figure out limits. In particular, limits that end up in indeterminate form. When I say by indeterminate form, I mean that when we just take the limit as it is, we end up with something like 0 over 0 or infinity over infinity or negative infinity over infinity.