• USD is the three-letter abbreviation for the US dollar.
  • The US dollar is the legal tender of the United States and also serves as the global reserve currency in international trade and financial markets.
  • The US dollar was once based on the gold standard, but since 1971 it has become a free-floating fiat currency.
  • The US dollar is the most traded currency on the international foreign exchange market, and the most active currency pair is the euro/US dollar.
  • the US dollar accounts for almost 90% of all foreign exchange transactions,