The foreign exchange (also known as forex or FX) market is a global marketplace for exchanging national currencies. Because of the worldwide reach of trade, commerce, and finance, forex markets tend to be the largest and most liquid asset markets in the world. Currencies trade against each other as exchange rate pairs.
Forex trading is similar to buying and selling other types of securities, like stocks. The main difference is that forex trading is done in pairs, such as EUR/USD (euro/U.S. dollar) or JPY/GBP (Japanese yen/British pound). When you make a forex trade, you sell one currency and buy another.