The primary currency used in the European Union is the Euro (€). It is the official currency in 19 of the 27 EU member countries, forming the Eurozone. The Euro was introduced in 1999 for electronic transactions and became physical currency in 2002. The currency facilitates trade and travel among member states, reducing currency exchange costs and promoting economic stability. It symbolizes a unified European economy and carries immense significance in global financial markets. The Euro is managed by the European Central Bank, which oversees monetary policy for the Eurozone to ensure economic stability and growth.