Vaporizer pens can be used to inhale a number of different materials. Often, people call vaporizer pens by names that indicate what they are used to vape. The three main types include: - The oil vaporizer pen, which is also called an oil pen or oil vape pen.
The United States is the world's largest economy with a GDP of approximately $18.56 trillion, notably due to high average incomes, a large population, capital investment, moderate unemployment, high consumer spending, a relatively young population, and technological innovation.
Measured on a purchasing power parity (PPP) basis that adjusts for price differences, China in 2014 stood as the largest economy in the world, surpassing the US for the first time in modern history. Still, China's per capita income is below the world average. After keeping its currency tightly linked to the US dollar for years, in July 2005 China moved to an exchange rate system that references a basket of currencies.