Manualism (hand music)
Manualism is the art of playing music by squeezing air through the hands. Because the sound produced has a distinctly flatulent tone, such music is usually presented as a form of musical comedy or parody. The musical performer is called a manualist, who may perform a cappella or with instrumental accompaniment.
Playing recognizable tunes by squeezing the hands together is extremely difficult, and takes many years of practice and even then is still difficult to perform. As a result, there are very few manualists performing on stage.