The Aztec economy was based on three things: agricultural goods, tribute, and trade.
Incan males were required to provide physical labor to the state for a set number of days, sometimes as much as two-thirds of the year. They built public buildings and palaces, as well as an extensive system of roads (14,000 miles in all), which linked the empire together and allowed for its ongoing expansion. In return, the government provided all the basic necessities of life; food, clothing, tools, housing, etc. No money changed hands.
