According to the book, it means: a standardized contract for physical delivery at some time in the future is determined at the current price. Understanding this meaning has several meanings:

1) The price is fixed now. Then even if the physical price rises or falls in the future, the delivery price will remain unchanged;

2) The physical delivery time is fixed. For example, the copper futures contract CU 1 109 is scheduled to be delivered in September of 1 1.

3) Standardized contracts. The contract terms and physical quality specifications are standard, which is convenient for large-scale transactions and delivery at the same price.