The modern foreign exchange market began forming during the 1970s. This followed three decades of government restrictions on foreign exchange transactions under the Bretton Woods system of monetary management, which set out the rules for commercial and financial relations among the world's major industrial states after World War II. Countries gradually switched to floating exchange rates from the previous exchange rate regime, which remained fixed per the Bretton Woods system.
A trader thinks that the European Central Bank (ECB) will be easing its monetary policy in the coming months as the Eurozone’s economy slows. As a result, the trader bets that the euro will fall against the U.S. dollar and sells short €100,000 at an exchange rate of 1.15. Over the next several weeks the ECB signals that it may indeed ease its monetary policy. That causes the exchange rate for the euro to fall to 1.10 versus the dollar. It creates a profit for the trader of $5,000.
Forex is a portmanteau of foreign currency and exchange. Foreign exchange is the process of changing one currency into another currency for a variety of reasons, usually for commerce, trading, or tourism. According to a recent triennial report from the Bank for International Settlements (a global bank for national central banks), the average was more than $5.1 trillion in daily forex trading volume.