Forex trading, or FX trading, involves buying and selling different currencies with the aim of making a profit. At its core, forex trading is about capturing the changing values of pairs of currencies. For example, if you think the Euro will increase in value against the U.S. Dollar, a speculator might buy Euros with Dollars. If the Euro's value rises on a relative basis (the EUR/USD rate), you can sell your Euros back for more Dollars than you initially spent, thus making a profit.