The format of "Let's Make a Deal" involves selected members of the studio audience, referred to as "traders," making deals with the host. In most cases, a trader will be offered something of value and given a choice of whether to keep it or exchange it for a different item. The program's defining game mechanism is that the other item is hidden from the trader until that choice is made. The trader thus does not know if they are getting something of greater value or a prize that is referred to as a "zonk," an item purposely chosen to be of little or no value to the trader.