Disklavier is the brand name for a group of piano

Piano

The piano is a musical instrument played by means of a keyboard. It is one of the most popular instruments in the world. Widely used in classical and jazz music for solo performances, ensemble use, chamber music and accompaniment, the piano is also very popular as an aid to composing and rehearsal...

-related products made by Yamaha Corporation. It was introduced in the United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 in 1987.

The various forms of Disklavier are essentially modern piano

Piano

The piano is a musical instrument played by means of a keyboard. It is one of the most popular instruments in the world. Widely used in classical and jazz music for solo performances, ensemble use, chamber music and accompaniment, the piano is also very popular as an aid to composing and rehearsal...

s that use electromechanical solenoids and optical sensors connected to LED

Light-emitting diode

A light-emitting diode is a semiconductor light source. LEDs are used as indicator lamps in many devices and are increasingly used for other lighting...

s allowing them to play notes and use the pedals independently of any human operator. Most models are based upon real acoustic pianos and have been engineered such that the sensors and electromechanical elements do not interfere with or affect the normal playing of the instrument.