Capitalism is the name of the hierarchical system that is build upon the ownership of property.It is also a general term that is used to define current free market economy.
Capitalism is said to be there since the foundation of human civilization. It has been started since the first humans had proclaimed stuff as their property, created their civilizations around those and formed the first classes within those groups. It is said that if those first people won't proclaim property but share it among each other, there won't be capitalism but Communism in this planet. 
The term is firstly used at Karl Marx's book called "Das Kapital", as the system of property that we have.
- Economic and Philosophic Manuscripts of 1844 - Karl Marx