Swaps are interest rate differentials and commonly relevant in the currency markets. Of course, brokers who offer CFD’s also levy swap rates. If you are an intra-day trader where you close your trades by the end of the day, swap rates are irrelevant. However, if you are a swing trader and tend to keep your position open over a period of time, you must pay attention to the swap rates as they can add or subtract a small, yet significant amount to your trade.