Capitalism is an economic and political system where a county's trade and industry are controlled by private citizens rather than the state. America is an example of a capitalism system where people can own their own business for profit.
Socialism is an economic and political theory of social organization where industry is controlled by the community. Cuba is an example of a socialims system where the economy is controlled by the state.
Communism is a politcal theory for a class system where everything is publicly owned and people are payed based on their abilities and need. China is an example of communism where everyone works for the common good.