Margin system. According to the Futures and Derivatives Law, a margin system is implemented in futures trading, and futures settlement institutions collect margins from settlement participants, who collect margins from traders. The deposit is used for settlement and performance guarantee. Margin system means that in futures trading, traders must pay a certain amount of margin in accordance with the provisions of futures exchanges as financial guarantee for their performance of futures contracts. Margin system is one of the core systems of futures trading settlement, which aims to ensure the performance of futures contracts and reduce the risk of default. According to the provisions of the Futures and Derivatives Law, a margin system is implemented in futures trading, and futures settlement institutions collect margins from settlement participants, who collect margins from traders. The deposit is used for settlement and performance guarantee, that is, in futures trading, if the trader fails to fulfill the obligations of the futures contract, the settlement participants will use the collected deposit to make compensation.