Gold bullion standard refers to a monetary system in which the value of a country's currency is based on a fixed amount of gold. Synonyms for this term include the gold standard, gold exchange standard, and gold-reserve currency standard. The gold standard was the dominant monetary system during the late 19th and early 20th centuries, providing global economic stability. However, the gold standard became impractical during the modern era, leading countries to shift to a fiat currency system. Despite the popularity of fiat currencies, the concept of the gold standard remains relevant in economics discussions as a monetary system that ensures stable exchange rates and low inflation.