The Euro is the official currency of the European Union, and it is used as a unit of account for investing and financial markets. It is the second-largest reserve currency in the world, after the US dollar. The Euro is used to facilitate international transactions and investments, as it is accepted in nearly all EU countries, as well as many other nations. Investors use the Euro to buy and sell stocks, bonds, commodities, and other investments. It is also used to price derivatives, such as options and futures contracts. The Euro helps to provide stability in global financial markets, making it an attractive currency for investors.