The bassoon is a woodwind instrument in the double reed family, which plays in the tenor and bass ranges. It is composed of six pieces, and is usually made of wood. It is known for its distinctive tone color, wide range, versatility, and virtuosity. It is a non-transposing instrument and typically its music is written in the bass and tenor clefs, and sometimes in the treble. There are two forms of modern bassoon: the Buffet (or French) and Heckel (or German) systems. It is typically played while sitting using a seat strap, but can be played while standing if the player has a harness to hold the instrument. Sound is produced by rolling both lips over the reed and blowing direct air pressure to cause the reed to vibrate. Its fingering system can be quite complex when compared to those of other instruments. Appearing in its modern form in the 19th century, the bassoon figures prominently in orchestral, concert band, and chamber music literature, and is occasionally heard in pop, rock, and jazz settings as well. One who plays a bassoon is called a bassoonist.