This document provides an introduction to different economic systems, including traditional, command, and market economies. It focuses on describing the US market economy. Key aspects of the US market economy include private property, profit motive, competition between businesses, and freedom of choice for consumers and workers. While the US has a predominantly market-based system, it also has some regulations and government-operated enterprises, making it a mixed economic system. Many formerly command-controlled economies are moving toward market-based systems.