Foreign exchange option, also known as currency option, refers to the option that the buyer of a contract buys or sells a certain amount of foreign exchange assets at the specified exchange rate on a future agreed date or within a certain period after paying a certain option fee to the seller.

In this process, the buyer's option means that the buyer has the right to buy at maturity without obligation, and the buyer cannot exercise the right (give up buying) at maturity. The holder of foreign exchange (currency) is the seller, and the holder will not be changed until the option expires and the buyer decides to exercise it.