The Euro is the official European currency that has been in operation in most European Union countries since January 1, 2002, although it had already been introduced as a currency in 1999.
The aim of the single currency was both to facilitate transactions between the member countries of the union and to create a currency that could compete on an equal footing with the dollar.
The monetary policy of the euro zone is carried out by the ECB (European Central Bank).
You can see its evolution in the euro exchange rate against the dollar