International reserves refer to foreign exchange assets such as various currencies and gold owned by the state, aiming at coping with external economic risks and maintaining the balance of international payments and currency stability. The functions of international reserves are various, mainly including the following aspects:

1. international payment settlement: international reserves can be used for cross-border payment settlement to ensure the smooth progress of international trade and investment activities. For example, when a country's currency is at risk of devaluation, its international reserves can be used to make up for the payment gap and ensure that international trade is not affected.

2. Investment and risk management: International reserves can be used for various investment and risk management activities. For example, a country can use part of its foreign exchange reserves to invest in bonds, stocks and funds of other countries in order to obtain higher returns. At the same time, reserves can also be used to hedge foreign exchange fluctuations and economic risks.

3. Monetary policy support: International reserves can also be used to support national monetary policies and maintain monetary stability. For example, when there are problems such as excessive money supply or inflation in the domestic market, the state can stabilize the exchange rate and price level by increasing foreign exchange reserves.

4. Crisis prevention and coordination: International reserves can also be used for crisis prevention and coordination. For example, when a country faces an external economic crisis, other countries can provide it with emergency assistance, including foreign exchange reserves and economic assistance.

5. International reputation and authority: International reserves are a symbol of a country's comprehensive strength and reputation. Having strong reserves can improve the country's international status and influence, and enhance the country's right to speak.

To sum up, the functions of international reserves are various, including international payment and settlement, investment and risk management, monetary policy support, crisis prevention and coordination, international reputation and authority, etc. It is very important for a country to maintain an appropriate reserve level, which can help it cope with external economic risks and challenges and ensure the stability and sustainable development of its economy.