A brass instrument is a musical instrument (usually made of brass) that is played by blowing into a mouthpiece. The air travels through a series of tubes and out of a funnel-shaped endpiece, producing a loud, sustained note. The note produced can be altered by blowing harder or softer, by altering the position of the lips, or (on some instruments) by pressing one or more valves. The trombone also has a sliding section that changes the note by increasing and decreasing the length of tubing.
Brass instruments make up the loudest section of the modern orchestra. Their raucous tone also makes them suitable for military bands and fanfares. They are also used in jazz and popular music, particularly ska, funk and Latin-influenced styles.
The orchestral brass instruments are the trumpet, trombone, tuba and French horn. Others include the bugle, sousaphone and euphonium. Note that the saxophone is a woodwind instrument, not brass, even though it is actually made of brass, because its sound is produced by a vibrating reed, although in jazz bands it is often grouped with brass instruments in the horn section.