Traders in the futures market can be roughly divided into three categories: the first category is spot traders related to the underlying assets who use the futures market to hedge, that is, hedgers; The second category is traders who try to take advantage of the volatility of futures prices to buy from low to high and obtain trading profits, that is, speculators; The third category is the traders who use the unreasonable price difference between related tradable assets to carry out arbitrage trading, that is, arbitrage traders.