there are three types of swaps, namely spot-to-forward swaps, one-day swaps and forward-to-forward swaps. Among them, the spot-to-forward swap transaction refers to selling or buying forward foreign exchange of the same currency while buying or selling a certain spot foreign exchange, which is the most common transaction method in swap transactions, and the transaction is divided into pure overdue and scattered swap transactions according to different participants; One-day swaps can be divided into three types: today, tomorrow, the day after tomorrow and the day after spot. Forward-to-forward swap refers to buying and selling forward foreign exchange in the same currency but with different delivery periods.