Futures trading mainly has the following systems: ① margin system. In futures trading, any trader must pay a certain proportion (usually 5% ~ 10%) of the value of the futures contracts he buys and sells. ② Daily settlement system, also known as daily mark-to-market system. At the end of daily trading, the Exchange will settle the profit and loss, trading margin, handling fees, taxes and other expenses of all contracts according to the settlement price of the day, and transfer accounts receivable and payable at the same time, so as to increase or decrease the settlement reserve of members accordingly. ③ Position limit system. The exchange stipulates the maximum amount of contract speculative positions that members or customers can unilaterally hold. (4) The declaration system for large households is closely related to the position limit system, which is a system to prevent large households from manipulating market prices and control market risks. ⑤ Compulsory liquidation system. When members and customers violate the rules, the exchange will implement compulsory liquidation of relevant positions.