Dollar
The currency used is the same one as most of the European Union countries: The EURO!
Euro.
There is no such thing as a euro dollar. What you are referring to is the euro, which is the name of a currency used in 17 of Europe's countries.
No. Canadian dollar.
There is no such thing as the German dollar. The currency in German is the Euro (symbol '€'). Currently (2012), USD 1 = € 0.77
The currency of Italy is the Euro; there is no such thing as an Italian dollar.
The US Dollar.
Irelands currency is the Euro, which is stronger.
Dollar and Euro
As of today's date which is August 18, 2014 one Euro is equal to one dollar and thirty four cents. The Euro is the currency which replaced the currency of several European countries.
20 Euro dollars. You will have to google for currency exchange rates.CorrectionThere's no such thing as a European 20 dollar bill or a "euro dollar". The currency is simply called the euro. The remainder of the answer is correct though, because exchange rates change every day.
There is $1.36 for every one euro. Euro is the currency that is used in Europe and the United States uses the dollar as their currency.