Arefrigerator(oftencalleda"fridge"forshort)isacoolingappliancecomprisingathermallyinsulatedcompartmentandamechanismtotransferheatfromittotheexternalenvironment,coolingthecontentstoatemperaturebelowambient.Refrigeratorsareextensivelyusedtostorefoodswhichdeteriorateatambienttemperatures;spoilageduetobacterialgrowthandotherprocessesismuchsloweratlowtemperatures.Devicesdescribedas"refrigerators"maintainatemperatureafewdegreesabovethefreezingpointofwater;similardeviceswhichmaintaintemperaturesbelowthefreezingpointofwaterarecalled"freezers".Therefrigeratorisarelativelymoderninventionamongstkitchenappliances.Itreplacedthecommoniceboxwhichhadbeenahouseholditemforalmostacenturyandahalfprior,andissometimesstillcalledbytheoriginalname"icebox".