So we're going to look at three economic systems, maybe four, yeah. We're going to look at traditional economic systems, developing then through trade into market-based economic systems, capitalism then. Command economic systems, which is like communism, and then mixed economic systems. So each one, just a few minutes, we're going to kind of go over the big idea and then give you some examples of the history and see if that can't hook you up with a better grade. So let me go find a traditional economic system and giddy up, we'll get going. So traditional economic systems are based basically around agriculture and the barter system. So we don't have cash and we don't have banks yet, so basically kind of an individual kind of farming idea where people are self-sufficient to a certain degree in their communities.