A reed is a piece of dry bamboo that is used in some musical instruments such as saxophones, clarinets and oboes. The musician blows air through the mouthpiece where the reed is firmly placed, and the air makes the reed vibrate; this vibration in the mouthpiece produces sound all along the instrument, which is changed into specific musical notes depending on the physical nature of the instrument.
Musical instruments that use reeds are members of the woodwind family, because many years ago the instruments were all made of wood. Today the instruments can be made of metal (brass, silver, gold), wood, or a hard plastic made to look like wood.
The bassoon family of instruments and the oboe family of instruments play with a double reed. Players play through blowing air through the double reed, making the reeds vibrate. A mouthpiece is not needed.
Bassoon double reeds.
Reed (instrument) for Kids. Kiddle Encyclopedia.