Expiry
Expiry is the date on which a futures contract stops trading and open positions must be settled, either by delivery of the commodity or by cash payment.
Every futures contract has a last day of trading, after which open positions must be resolved, either through physical delivery of the commodity or cash settlement against a reference price. Most traders never reach that date: they close their position beforehand by taking an offsetting trade, leaving delivery to the smaller number of participants actually equipped to send or receive the physical commodity.
Trading volume and price volatility often pick up in the days just before expiry, as the remaining open positions are unwound or rolled into a later contract. The specific expiry date and the rules for what happens afterward, including the delivery month if the contract is delivery-settled, are fixed by the exchange when the contract is first listed, not negotiated by individual traders.