For example, if you want to buy copper with a value of 500,000 yuan, you only need 50,000 yuan (that is, pay a deposit of 10%) to trade. If you make money, then you use 500 thousand to calculate the income (earn a lot), but the loss is also calculated with this 500 thousand, which means a lot of losses. It's probably a negative number, which means you have to add a deposit. So it's a lever. It is precisely because of the existence of leverage principle that futures can buy and sell many futures with little money, which attracts many people to speculate in order to get huge profits with little money. But high returns are accompanied by high risks.