Piano | Piano History |

The piano (an abbreviation of pianoforte) is a musical instrument played using a keyboard. It is widely used in classical and jazz music for solo performances, ensemble use, chamber music and accompaniment and for composing and rehearsal. Although the piano is not portable and often expensive, its versatility and ubiquity have made it one of the world's most familiar musical instruments.

A piano usually has a protective wooden case surrounding the soundboard and metal strings, and a row of black and white keys (52 white keys and 36 black keys). The strings are sounded when the keys are pressed down, and are silenced when the keys are released. The note can be sustained, even when the keys are released, by the use of pedals at the bottom of the piano.

Pressing a key on the piano's keyboard causes a padded (often with felt) hammer to strike steel strings. The hammers rebound, and the strings continue to vibrate at their resonant frequency. These vibrations are transmitted through a bridge to a soundboard that more efficiently couples the acoustic energy to the air. The sound would otherwise be no louder than that directly produced by the strings. When the key is released, a damper stops the string's vibration and the sound. Despite the fact that a piano has strings, it is usually classified as a percussion instrument because the strings are struck rather than plucked (as with a harpischord or spinet). See the article on piano key frequencies for a picture of the piano keyboard and the location of middle C. In the Hornbostel-Sachs system of instrument classification, pianos are considered chordophones.

The word piano is a shortened form of pianoforte (PF), the Italian word for the instrument (which in turn derives from the previous terms gravicembalo col piano e forte and fortepiano). The Italian musical terms piano and forte indicate "soft" and "strong" respectively, in this context referring to the variations in sound volume the instrument produces in response to a pianist's touch on the keys: the greater the velocity of a key press, the greater the force of the hammer hitting the strings, and the louder the sound of the note produced.

The piano was founded on earlier technological innovations. The first string instruments with struck strings were the hammered dulcimers. During the Middle Ages, there were several attempts at creating stringed keyboard instruments with struck strings. By the 17th century, the mechanisms of keyboard instruments such as the clavichord and the harpsichord were well known. In a clavichord, the strings are struck by tangents, while in a harpsichord they are plucked by quills. Centuries of work on the mechanism of the harpsichord in particular had shown the most effective ways to construct the case, soundboard, bridge, and keyboard for a mechanism intended to hammer strings.

The invention of the modern piano is credited to Bartolomeo Cristofori (1655–1731) of Padua, Italy, who was employed by Ferdinando de' Medici, Grand Prince of Tuscany, as the Keeper of the Instruments; he was an expert harpsichord maker, and was well acquainted with the body of knowledge on stringed keyboard instruments. It is not known exactly when Cristofori first built a piano. An inventory made by his employers, the Medici family, indicates the existence of a piano by the year 1700; another document of doubtful authenticity indicates a date of 1698. The three Cristofori pianos that survive today date from the 1720s.

While the clavichord allowed expressive control of the sound volume and sustain, it was too quiet for large performances. The harpsichord produced a sufficiently loud sound, but had little expressive control over each note. The piano was probably formed as an attempt to combine loudness with control, avoiding the trade-offs of available instruments.

Cristofori's great success was solving, with no prior example, the fundamental mechanical problem of piano design: the hammer must strike the string, but not remain in contact with it (as a tangent remains in contact with a clavichord string) because this would damp the sound. Moreover, the hammer must return to its rest position without bouncing violently, and it must be possible to repeat a note rapidly. Cristofori's piano action was a model for the many approaches to piano actions that followed. Cristofori's early instruments were made with thin strings, and were much quieter than the modern piano, but much louder and with more sustain in comparison to the clavichord—the only previous keyboard instrument capable of dynamic nuance via the keyboard.