This document discusses different types of monopolies including those that emerge from owning essential resources, are created by government through laws like patents and copyrights, and natural monopolies where one firm can supply a good or service to the entire market at lower cost than competitors. It defines monopoly as a market with only one seller and no close substitutes where there is no free entry for other firms. Government-created monopolies allow higher prices to encourage creative activity while natural monopolies exist in industries where size of the market determines if it is competitive.