Reserve currency

A reserve currency (or anchor currency) is a foreign currency that is held in significant quantities by central banks or other monetary authorities as part of their foreign exchange reserves. 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 first half of the 20th century. However, by the middle of the 20th century, the United States dollar had become the world's dominant reserve currency. The world's need for dollars has allowed the United States government to borrow at lower costs, giving the United States an advantage in excess of US$100 billion per year. Reserve currencies have come and gone with the evolution of the world’s geopolitical order. International currencies in the past have (excluding those discussed below) included the Greek drachma, coined in the fifth century B.C.E., the Roman denari, the Byzantine solidus and Islamic dinar of the middle-ages and the French franc. The Venetian ducat and the Florentine florin became the gold-based currency of choice between Europe and the Arab world from the 13th to 16th centuries, since gold was easier than silver to mint in standard sizes and transport over long distances. It was the Spanish silver dollar, however, which created the first true global reserve currency recognized in Europe, Asia and the Americas from the 16th to 19th centuries due to abundant silver supplies from Spanish America. While the Dutch guilder was a reserve currency of somewhat lesser scope, used between Europe and the territories of the Dutch colonial empire from the 17th to 18th centuries, it was also a silver standard currency fed with the output of Spanish-American mines flowing through the Spanish Netherlands.