Futures and spot are completely different. Spot is actually a tradable commodity. Futures are mainly not commodities, but standardized tradable contracts with some bulk products such as cotton, soybeans and oil and financial assets such as stocks and bonds as the targets. This subject matter can be commodities (such as gold, crude oil, agricultural products), financial instruments or financial indicators. The delivery date of futures can be one week later, one month later, three months later or even one year later. A contract or agreement to buy or sell futures is called a futures contract. The place where futures are bought and sold is called the futures market. Investors can invest or speculate in futures. Improper speculation on futures, such as short selling stocks, will lead to financial market turmoil. Futures, based on stock index, can not only provide effective hedging tools for stock investors, but also provide experience for the timely introduction of financial derivatives such as foreign exchange futures in the future, which is of great significance to the development of the stock market. Using stock index futures to hedge the stock index and its stocks can effectively avoid the risks caused by stock index fluctuation and price fluctuation in the stock market. The timely introduction of stock index futures will play an important role in promoting the development of China's capital market. Generally speaking, futures trading has two functions: one is price discovery function, and the other is hedging function. As a kind of financial futures, stock index futures also have two functions: price discovery and hedging.