The U.S. dollar is the most widely used currency in international trade, even in trade between countries other than the United States. It is the unit in which countries often express their exchange rate. Countries maintain their “official” exchange rates by buying and selling U.S. dollars and hold dollars as their primary reserve currency.
Which currency is used the most in international trade?
When were coins first used as money?
The use of metal for money can be traced back to Babylon, prior to 2000 BCE. Standardization and certification in the form of coinage did not occur except perhaps in isolated instances until the 7th century BCE. Historians generally ascribe the first use of coined money to Croesus, king of Lydia, a state in Anatolia.