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Related to U.S. Dollar: U.S. Dollar Index
The currency of the United States. First issued in 1792, it is the currency used most often in international transactions. After World War II, most world currencies were pegged to the dollar, which was pegged to gold. In 1971, the dollar became a fiat currency. Nevertheless, many currencies are still pegged to the dollar, and it is one of the most important reserve currencies in the world.