Trombone

  The trombone (Ger. Posaune, Sp. trombón) is a musical instrument in the brass family. Like all brass instruments, sound is produced when the player’s vibrating lips (embouchure) cause the air column inside the instrument to vibrate. The trombone is usually characterised by a telescopic slide with which the player varies the length of the tube to change pitches, although the valve trombone uses three valves like those on a trumpet.
The word trombone derives from Italian tromba (trumpet) and -one (a suffix meaning "large"), so the name literally means "large trumpet". Trombones and trumpets share the important characteristic of having predominantly cylindrical bores. Therefore, the most frequently encountered trombones—the tenor and bass trombone—are the tenor and bass counterparts of the trumpet. Trombone music, along with music for euphonium and tuba, is typically written in concert pitch while trumpet music is transposed to B♭, although exceptions do occur, the most notably being in brass band music. Most trombones are pitched in B♭, an octave below the trumpet and an octave above the tuba.

Trombone

Copied from: http://en.wikipedia.org/wiki/Trombone