Euro (EUR)

The euro (currency sign: €; banking code: EUR) is the official currency of the Eurozone (also known as the Euro Area), which consists of the European states of Austria, Belgium, Finland, France, Germany, Greece, Ireland, Italy, Luxembourg, the Netherlands, Portugal, Slovenia, and Spain, and will extend to include Cyprus and Malta from 1 January 2008.
It is the single currency for more than 317 million Europeans. Including areas using currencies pegged to the euro, the euro directly affects more than 480 million people worldwide.
With more than €610 billion in circulation as of December 2006 (equivalent to US$802 billion at the exchange rates at the time), the euro surpasses the U.S. dollar in terms of combined value of cash in circulation.
While all European Union (EU) member states are eligible to join if they comply with certain monetary requirements, not all EU members have chosen to adopt the currency. All nations that have joined the EU since the 1993 implementation of the Maastricht Treaty have pledged to adopt the euro in due course. Maastricht obliged current members to join the euro; however, the United Kingdom and Denmark negotiated exemptions from that requirement for themselves. Sweden turned down the euro in a 2003 referendum, and has circumvented the requirement to join the euro area by not meeting the membership criteria.
Several small European states (The Vatican, Monaco, and San Marino), although not EU members, have adopted the euro due to currency unions with member states. Andorra, Montenegro, and Kosovo have adopted the euro unilaterally.