Capitalism is characterized by a market economy relying on the use of capital and a set of ideological premises. The use of capital for mass production and division of labor is found to be essential. The market economy relies on the price system to express the consumer sovereignty which dictates to businesses what they should produce as if guided by an invisible hand.
The United States and all the other Western countries are relying on a system where capital, i.e. means of production, are freely owned by private individuals. This is one of the major differences with State ownership in socialist countries.