1. Free foreign exchange refers to foreign currency or foreign currency payment means that can be freely exchanged, flowed and transferred in the international economic field.

2. Bookkept foreign exchange shall be used in the payment agreement signed by the two governments, and shall not be freely converted into other countries' currencies or paid to a third country without the approval of the currency issuing country.

3. Trade foreign exchange refers to the foreign exchange received and paid in import and export trade, including goods and related auxiliary expenses, such as freight, insurance, publicity and promotion fees, etc. As the main content of international economic exchange is international trade, trade foreign exchange is the main source and use of a country's foreign exchange.

4. Non-trade foreign exchange refers to the foreign exchange received and paid by other parties except import and export trade and capital export/input, including labor service foreign exchange, remittance, donation foreign exchange and aid foreign exchange. Generally speaking, non-trade foreign exchange is the secondary source and use of a country's foreign exchange; There are some exceptions, such as Switzerland, where non-trade foreign exchange is the main source and use of foreign exchange.

5. Spot foreign exchange refers to foreign exchange delivered on the same day or within two business days after a foreign exchange transaction is concluded. The so-called delivery refers to the exchange of ownership of local currency and foreign currency between the local currency owner and the foreign currency owner, that is, the actual payment in foreign exchange transactions.

6. Forward foreign exchange refers to the foreign exchange that the buyer and the seller do not need to deliver immediately, but only need to sign a sales contract and agree to deliver at a certain time in the future (two business days). Forward foreign exchange is usually caused by forward payment terms in international trade settlement; The purpose of buying and selling forward foreign exchange is mainly to avoid or reduce the risk loss caused by exchange rate changes.