The 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 (that's the "wind" in "woodwind") and opening or closing the holes with your fingers to change the pitch. Metal caps called keys cover the holes of most woodwind instruments.
The mouthpieces for some woodwinds, including the clarinet, oboe and bassoon, use a thin piece of wood called a reed, which vibrates when you blow across it. The clarinet uses a single reed made of one piece of wood, while the oboe and bassoon use a double reed made of two pieces joined together. Just as with the stringed instruments, the smaller woodwinds play higher pitches while the longer and larger instruments play the lower notes. The woodwind family of instruments includes, from the highest sounding instruments to the lowest, the piccolo, flute, oboe, English horn, clarinet, E-flat clarinet, bass clarinet, bassoon and contrabassoon.