foreign currency trading involves trades in which one party purchases a number of one currency by paying in a quantity of another currency.
The foreign currency market is a global decentralized money market for the trading of currencies. Around the world various financial centers act as hubs for trading between a wide range of different types of purchasers and sellers 24 hours a day, except weekends. It is the currenecy market that gives the value of one nation's currency relative to another.