1. The main futures contract refers to the contract with the largest position. Under normal circumstances, the contract with the largest position is also the largest.
2. "Main company" represents the continuous quotation of main contracts in different periods.
3. It should be noted that futures are different from stocks, because futures contracts are delivered after the last trading day of the contract, so the life cycle of the main futures contract is limited, and it will change to the later contract with the passage of time, which is what we usually call changing the moon.