Answer: Marxism, also known as communism. Marx himself also referred to his theories as "scientific socialism."
Details:
Karl Marx usually receives credit for what we know as Marxism or communism ... but we might properly also call it "Marx/Engels-ism" -- because Karl Marx's close partner in founding the movement was Friedrich Engels. They were co-writers of many of the key founding works of communist thought, such as "The Communist Manifesto" and the multi-volume set of books called, Capital. (The title in German was Das Kapital -- you might have heard of that famous work.)
Marx and Engels proposed a communist world order in which there would not be private property, but all would be shared communally. Each person would contribute according to his ability and receive from the community according to his need. The means of production would be owned by the people themselves who produced goods, rather than having capital (investment) in the hands of a business owners who controlled and dominated the working class.
