The trombone is a musical instrument in the brass family. As with all brass instruments, the sound is produced when the player's vibrating lips cause the air column inside the instrument to vibrate. Beginners will need to buy a method book from Kjos's Traditional of Excellence book 1. Intermediate will need to buy method book from Kjos's Traditional of Excellence book 2 or 3. For Advance, will advise according to the standard of playing.