Foreign Exchange ( FOREX ) is the arena where a nation's currency is exchanged for that of another. The foreign exchange market is the largest financial market in the world. But Unlike other financial markets, the Forex market has no physical location or no central exchange. FOREX operates through a global network of banks, corporations and individuals trading one currency for another. The lack of a physical exchange enables the Forex market to operate on a 24-hour basis, spanning from one zone to another in all the major financial centers.