Answer:
1. The proletariat is the social class of wage-earners, those members of a society whose only possession of significant economic value is their labour power. A member of such a class is a proletarian.
2. The bourgeoisie is a sociologically defined social class, equivalent to the middle or upper middle class. They are distinguished from, and traditionally contrasted with, the proletariat by their relative affluence, and their cultural and financial capital.
3. Communism is a philosophical, social, political, and economic ideology and movement whose goal is the establishment of a communist society, namely a socioeconomic order structured upon the ideas of common or social ownership of all property and the absence of social classes, money, and the state.
4. Capitalism is an economic system based on the private ownership of the means of production and their operation for profit. Central characteristics of capitalism include capital accumulation, competitive markets, price system, private property, property rights recognition, voluntary exchange, and wage labor.
