String instruments are usually long necked and that produce sound through hollow cavities from tightly pulled strings. The strings are separated into three categories: plucked, as with a guitar, shimasen or sitar; struck, as with certain types of violas and violins; or bowed, as with cellos and the double bass.
The woodwind family, sometimes called the reed family, comprises instruments that produce sound when the musician blows into a mouthhole with a reed, as with the clarinet, saxophone or oboe; across an edged slit, as with a recorder; or across an open hole, as with a fife or flute.
Percussive instruments are thought to be some of the oldest known to human civilization, comprised of little more than a stretched material over a hollow vessel to produce a simple drum. Many types of drums use the particular shaping and material of the body in order to produce a certain type of sound, such as the unique steel drum, made with a thin sheet metal head and a metal barrel body.
Brass instruments are distinct from woodwinds not necessarily in what materials they are made of but in how sounds are produced. Brass instruments are valved or slid, involving simple mechanics that change the length of the tube that lip blown air travels through. Examples include trumpets, trombones and tubas.
If percussion instruments are among the oldest man-made instruments, the human voice is undoubtedly the oldest. Through a combination of training and fortunate genetics, a human voice can have many different qualities and registers that can be complemented or contrasted with various instruments. The 12-tone scale, upon which some music is composed, is based on the human voice.