Opening a position, also known as opening a position, refers to the new purchase or sale of a certain number of futures contracts by traders. In the futures market, buying and selling a futures contract is equivalent to signing a forward delivery contract. If traders keep futures contracts until the end of the last trading day, they must settle futures transactions by physical delivery or cash settlement. However, only a few people make physical delivery, and most speculators and hedgers usually choose to sell their futures contracts or buy back their futures contracts before the end of the last trading day.

Closing position refers to the behavior of investors buying or selling stock index futures contracts with the same variety, quantity and delivery month but in the opposite direction in order to close the stock index futures trading. Closing in futures trading and selling in stock trading are the same concept. Because futures trading has a two-way trading mechanism, there are two kinds of closing positions: buying and closing positions (corresponding to selling and opening positions) and selling and closing positions (corresponding to buying and opening positions).

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