A counter offer is a new offer that is made in response to a previous offer. It's different from the original offer because it includes different terms or conditions. For example, if someone makes an offer to buy your car for $10,000, and you counter with an offer to sell it for $12,000, the counter offer is a new and different offer than the original one. The original offer is no longer valid, and the parties must either accept the counter offer or make a new offer.