Currency prices are constantly moving, so the trader may decide to hold the position overnight. The broker will rollover the position, resulting in a credit or debit based on the interest rate differential between the Eurozone and the U.S. If the Eurozone has an interest rate of 4% and the U.S. has an interest rate of 3%, the trader owns the higher interest rate currency because they bought EUR. Therefore, at rollover, the trader should receive a small credit. If the EUR interest rate was lower than the USD rate then the trader would be debited at rollover.
When trading in the forex market, you're buying or selling the currency of a particular country, relative to another currency. But there's no physical exchange of money from one party to another. That's what happens at a foreign exchange kiosk—think of a tourist visiting Times Square in New York City from Japan. He may be converting his physical yen to actual U.S. dollar cash (and may be charged a commission fee to do so) so he can spend his money while he's traveling. But in the world of electronic markets, traders are usually taking a position in a specific currency, with the hope that there will be some upward movement and strength in the currency they're buying (or weakness if they're selling) so they can make a profit.
Fortunately, some of the differences between successful traders and those who lose money are no longer a secret. Through conducting an intense study of client behaviour, the team at FXCM has identified three areas where winning traders excel. While there is no "holy grail" for profitable forex trading, establishing good habits in regards to risk vs reward, leverage and timing is a great way to enhance your performance.