The woodwind instruments in this family all used to be made of wood, which gives them their name. Today, they are made of wood, metal, plastic or some combination. They are all basically narrow cylinders or pipes, with holes, an opening at the bottom end and a mouthpiece at the top. You play them by blowing air through the mouthpiece and opening or closing the holes with your fingers to change the pitch. Metal caps called keys cover the holes of most woodwind instruments.