Developed in 1841 by Adolphe Sax, the standard saxophone has 23 different keys. The instrument also contains two small speaker holes that assist the player in hitting notes in the upper register.
Each one of the keys features a soft leather pad, which creates an airtight seal. When the saxophone is at rest, some of the holes are open while others are closed. Each key is controlled by the press of a finger, and the right thumb of the saxophone player rests underneath the instrument to help provide balance. The saxophone is usually constructed of brass even though it is classified as a woodwind instrument.