Karl Marx was a German philosopher, economist, historian, and revolutionary socialist who lived from 1818 to 1883. He is renowned for his theories about capitalism and socialism. Some of his key ideas were that capitalism exploits workers for profit, inequality is inherent in the capitalist system as the wealthy bourgeoisie owns the means of production, and that communism is a classless system where the working class owns the means of production. He published the Communist Manifesto in 1848 which outlined his theories and called for working class revolution.