1。 Standardization. The price in the futures contract is the only variable, which is generated by public bidding, while the commodity variety, quantity, quality, grade, delivery time and delivery place of the futures contract are unique and unchangeable. It is uniformly stipulated by the futures exchange and listed by the state regulatory agency. 2。 Open. All transactions of futures contracts must be completed in the exchange, and cannot be traded privately. 3。 Trading mode. For the only variable: futures price, most foreign countries compete by public bidding, while all countries trade by computer. 4。 Futures contracts can fulfill or cancel their contractual obligations through the settlement of spot or hedging transactions.