Pianos

The piano is an acoustic, stringed musical instrument invented in Italy by Bartolomeo Cristofori around the year 1700 (the exact year is uncertain), in which the strings are struck by wooden hammers that are coated with a softer material. (Modern hammers are covered with dense wool felt; some early pianos used leather.) It is played using a keyboard, which is a row of keys (small levers) that the performer presses down or strikes with the fingers and thumbs of both hands to cause the hammers to strike the strings. 

A keyboard instrument is a musical instrument played using a keyboard, a row of levers which are pressed by the fingers. The most common of these are the piano, organ, and various electronic keyboards, including synthesizers and digital pianos. Other keyboard instruments include celestas, which are struck idiophones operated by a keyboard, and carillons, which are usually housed in bell towers or belfries of churches or municipal buildings. 

A synthesizer (also spelled synthesiser) is an electronic musical instrument that generates audio signals. Synthesizers generate audio through methods including subtractive synthesis, additive synthesis, and frequency modulation synthesis. These sounds may be shaped and modulated by components such as filters, envelopes, and low-frequency oscillators. Synthesizers are typically played with keyboards or controlled by sequencers, software, or other instruments, often via MIDI.