Trombone.

The trombone is a member of the brass family of musical instruments. It originated in the fifteenth century and is the only member of the brass section that uses a slide rather than valves to play different notes. Music played by a trombone is lower in tone than other members of the brass family such as the trumpet and serves to complement the higher tones. Once considered appropriate only for the accompaniment of church music, the inclusion of parts for the trombone in music by famous composers brought the instrument into the mainstream. It is now considered an important part of many types of musical ensembles, including orchestras and marching bands. A Tenor Trombone By w:user:Esolomon (File:Posaune.gif) [Copyrighted free use], via Wikimedia Commons A trombonist. By Htoo Tay Zar (Own work) [CC BY-SA 3.0 (http://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons