The euro (currency sign: €; banking code: EUR) is the official currency of the European states of Austria, Belgium, Finland, France, Germany, Greece, Ireland, Italy, Luxembourg, the Netherlands, Portugal, Slovenia and Spain - also known as the Euro zone - and is the single currency for more than 317 million people in Europe.
Including areas using currencies pegged to the euro, the euro affects more than 480 million people worldwide, with more than €610 billion in circulation as of December 2006. While all EU member states are eligible to join if they comply with certain monetary requirements, the euro is not used in all of the European Union as not all EU members have adopted the currency. All nations which have recently joined the EU are pledged to adopt the euro in due course, but the United Kingdom and Denmark are under no such obligation. Several small European states, like 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.