Futures contracts are standardized contracts made by exchanges, which stipulate to deliver a certain quantity and quality of goods at a specific time and place in the future. The main terms of a futures contract include: trading variety, trading unit, quotation unit, minimum change price, maximum fluctuation range of daily price, contract delivery month, trading time, last trading day, delivery date, delivery grade, delivery place, minimum margin, transaction cost, minimum delivery unit, delivery method and trading code.