Social stratification occurs when a distinct social hierarchy develops. Groups that have different amounts wealth and social status make up a hierarchy.
Economic systems are one of the themes in AP World History. These them includes control of resources, production of goods, consumption of products, trade routes, types of economic systems, and forced labor.
Technology and Innovation is one of the themes in AP World History. Technology refers to physical tools that help humans achieve goals or complete tasks. Innovation refers to new discoveries and improving on old processes.