The euro is the official currency of 19 of the 28 member states of the European Union. This group of states is known as the eurozone or euro area, and counts about 343 million citizens as of The euro, which is divided into 100 cents, is the second largest and second-most traded currency in the foreign exchange market after the United States dollar. The name euro was officially adopted on 16 December 1995 in Madrid. The euro was introduced to on 1 January