The three branches of the woodwind family have different sources of sound. Vibrations begin when air is blown across the top of an instrument, across a single reed, or across two reeds. Reeds are small pieces of cane. A single reed is clamped to a mouthpiece at the top of the instrument and vibrates against the mouthpiece when air is blown between the reed and the mouthpiece. Two reeds tied together are commonly known as a double reed. This double reed fits into a tube at the top of the instrument and vibrates when air is forced between the two reeds.
The oboe is similar to the clarinet in many ways. Both are made from wood and have metal keys that can produce many notes rapidly. Unlike the clarinet, the oboe does not have a mouthpiece, but has two reeds tied together. By placing them between one's lips and blowing air through them, the reeds vibrate and produce a sound.