The best way to begin to think about our economic system—and to understand ultimately how these systems interact with each other, and what information is relevant to our understanding of financial markets—is to divide our complex system into three main markets: Services, Products, and Financial. At its core, ultimately there are people (who create the demand that fuels the system), capital (used to clear the transactions), and buyers and sellers. The understanding of how these components work together and affect each other is the basis for understanding how to invest in these markets.