In American English, half-and-half is a carton in the shop: milk and cream mixed about fifty-fifty, poured into coffee or tea. It is richer than milk and thinner than cream. This is a United States supermarket word; British English does not really use it as the name of a dairy product — there, half and half can mean other 50/50 mixes, even two beers. In Taiwan you often will not find the same carton; mixing ordinary milk and fresh cream yourself is the idea. It is everyday and informal, not a fancy cooking term.

半奶半鮮奶油（美式咖啡用；不是台灣常說的「奶精」）