From the hospital appliances we use everyday to the state of the ark scientific instruments that span the galaxies or peer deep into the subatomic world this wide-ranging wonderful illustrated book exployers explicits and many technological that shape every modern Life. how does a refrigerator keep your food cold and your microwave heat it up? what keeps the sailboat of float or the airplane up in the sky? why don't hydraulic plants need any soil to grow? how does a CD player turn laser light into digital sound? these are just a few with a hundred of questions answered here in a clear concise text and more than 150 photographs diagrams that clarify basic site physiological principles and show how they are put to work in scores of machines. National Geographic