Futures hedging refers to the trading activities in which the futures market is used as a place to transfer the price risk, and the futures contract is used as a temporary substitute for buying and selling commodities in the spot market in the future, so as to insure the prices of commodities to be bought in the future. The basic feature of hedging is that the same commodity is bought and sold in the spot market and futures market at the same time, that is, at the same time of buying or selling the real thing, the same amount of futures is sold or bought in the futures market. After a period of time, when the price changes make the profit and loss in spot trading even, the losses in futures trading can be offset or compensated. Therefore, hedging mechanisms are established between "now" and "period" and between short-term and long-term to minimize price risk.