Stir-fry need is a term used to describe the necessary ingredients for making a stir-fry. The two main components are OIL and wok. OIL, with three letters, is a liquid fat that is used to cook food in a pan or wok. Wok, also with three letters, is a round-bottomed cooking vessel that is used to cook food over high heat. Stir-frying is a Chinese cooking technique that involves quickly cooking small pieces of food in a hot wok with OIL.