About USD and EUR
US Dollar (USD)
The US dollar is divided into 100 cents and is used in the United States and several other economies, and many tourist businesses elsewhere quote prices in dollars. When a card terminal in another country offers to charge you in dollars, that is usually a dynamic currency conversion with a poor rate; choose the local currency instead.
Euro (EUR)
The euro is shared by the euro-area countries of the European Union and is divided into 100 cents. Because many countries use it, one cash supply covers a multi-country trip. Prices are comparable in form across countries but not in level: the same coffee can cost far more in one euro country than in another.
Exchanging USD for EUR
The rate above is the mid-market rate for USD to EUR. Banks, card networks and exchange desks usually apply a margin or a fee, so compare the amount you would actually receive. If a terminal offers to charge you in USD instead of EUR, decline: that conversion normally uses a worse rate.