The currency used in the Eurozone is the euro, denoted by the symbol € and the code EUR. Introduced in 1999, the euro became a physical currency in 2002. It is used by 19 of the 27 European Union member states, forming a monetary union called the Eurozone. The euro aims to facilitate trade and investment between member countries by eliminating exchange rate fluctuations and simplifying transactions. It is one of the world's most widely traded currencies and has become a symbol of European integration. The European Central Bank is responsible for the monetary policy governing the euro.