Reserve Currency

A reserve currency is a foreign currency that is held by governments, central banks or other monetary authorities as part of their foreign exchange reserves.[1] The reserve currency can be used in international transactions, international investments and all aspects of the global economy. It is often considered a hard currency or safe-haven currency. The United Kingdom's pound sterling was the primary reserve currency of much of the world in the 19th century and the first half of the 20th century.[2] However, by the middle of the 20th century, the United States dollar had become the world's dominant reserve currency. https://en.wikipedia.org/wiki/Reserve_currency

• After World War II, the international financial system was governed by a formal agreement, the Bretton Woods system. Under this system, the United States dollar (USD) was placed deliberately as the anchor of the system, with the US government guaranteeing other central banks that they could sell their US dollar reserves at a fixed rate for gold.[12] In the late 1960s and early 1970s, the system suffered setbacks ostensibly due to problems pointed out by the Triffin dilemma—the conflict of economic interests that arises between short-term domestic objectives and long-term international objectives when a national currency also serves as a world reserve currency.[13] Additionally, in 1971 President Richard Nixon suspended the convertibility of the USD to gold, thus creating a fully fiat global reserve currency system. However, gold has persisted as a significant reserve asset since the collapse of the classical gold standard.
• At the beginning of the 21st century, gold and crude oil were still priced in dollars, which helps export inflation and has brought complaints about OPEC's policies of managing oil quotas to maintain dollar price stability.[58] Due to the Russian invasion of Ukraine and international sanctions, Russia has used the United Arab Emirates dirham as a neutral currency when selling oil to India.