A cooler, cool box, portable ice chest, ice box, chilly bin (in New Zealand), or ‘esky’ (Australia) most commonly is an insulated box used to keep food or drink cool. Ice cubes are most commonly placed in it to help the things inside stay cool. Ice packs are sometimes used, as they either contain the melting water inside, or have a gel sealed inside that stays cold longer than plain ice (absorbing heat as it changes phase). The portable ice chest was invented by Richard C.