The foreign exchange market, commonly referred to as Forex or FX, is where currencies are traded. This international market lacks a central marketplace. Instead, currency trading is conducted electronically over-the-counter (OTC). This means that all transactions occur via computer networks among traders worldwide rather than on one centralized exchange. The market is open 24 hours a day, five and a half days a week. Currencies are traded worldwide in the major financial centers of Frankfurt, Hong Kong, London, New York, Paris, Singapore, Sydney, Tokyo, and Zurich—across almost every time zone.