The document discusses the evolution of international monetary systems over time. It begins by defining money and its functions, then outlines several stages of international monetary systems: bimetallism before 1875, the classical gold standard from 1875-1914, the interwar period from 1915-1944, the Bretton Woods system from 1945-1972, and the current flexible exchange rate regime from 1973 onward. Each system is described in terms of the prevailing rules, features, and reasons for changes or demise over time. In particular, it focuses on the shift from the Bretton Woods dollar-pegged system to the current floating rate regime in the early 1970s.