Capitalism is the idea of a hands off kind of government. Although, there is no "perfect" Capitalisitic country. Although, the United States is described as a capitalistic country. The idea came from a scottish philosher, Adam Smith.
How is it Better?
Capitalism is way better because the other two have government regulations expecially with socialism since it is all Government. Without Capitalistic countries, countries would have to worship a hypocritic leader such as Kim Jong Un.