Piano

A piano is a keyboard instrument that produces sound when its keys are depressed, activating an action mechanism where hammers strike strings. Modern pianos have a row of 88 black and white keys, tuned to a chromatic scale in equal temperament. A musician who specializes in piano is called a pianist.

There are two main types of piano: the grand piano and the upright piano. The grand piano offers better sound and more precise key control, making it the preferred choice when space and budget allow. The grand piano is also considered a necessity in venues hosting skilled pianists. The upright piano is more commonly used because of its smaller size and lower cost.

When a key is depressed, the strings inside are struck by felt-coated wooden hammers. The vibrations are transmitted through a bridge to a soundboard that amplifies the sound by coupling the acoustic energy to the air. When the key is released, a damper stops the string's vibration, ending the sound. Most notes have three strings, except for the bass, which graduates from one to two. Notes can be sustained when the keys are released by the use of pedals at the base of the instrument, which lift the dampers off the strings. The sustain pedal allows pianists to connect and overlay sound, and achieve expressive and colorful sonority.

In the 19th century, influenced by Romantic music trends, the fortepiano underwent changes such as the use of a cast iron frame, which allowed much greater string tensions. Aliquot stringing gave grand pianos a more powerful sound, a longer sustain, and a richer tone. Later in the century, as the piano became more common it allowed families to listen to a newly published musical piece by having a family member play a simplified version.

The piano is widely employed in classical, jazz, traditional and popular music for solo and ensemble performances, accompaniment, and for composing, songwriting and rehearsals. Despite its weight and cost, the piano's versatility, the extensive training of musicians, and its availability in venues, schools, and rehearsal spaces have made it a familiar instrument in the Western world.

The piano was based on earlier technological innovations in keyboard instruments. The earliest known keyboard instrument was the Ancient Greek hydraulis, a type of pipe organ invented in the third century BC. Pipe organs had been used since antiquity, and as such the development of pipe organs enabled instrument builders to learn about creating keyboard mechanisms for sounding pitches. The first string instruments with struck strings were the hammered dulcimers, which were introduced in the Middle Ages in Europe. 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 developed. In a clavichord the strings are struck by tangents, while in a harpsichord they are mechanically plucked by quills when the performer depresses the key. Centuries of work on the mechanism of the harpsichord in particular had shown instrument builders the most effective ways to construct the case, soundboard, bridge, and mechanical action for a keyboard intended to sound strings.

The English word piano is a shortened form of the Italian pianoforte, derived from gravecembalo col piano e forte ("harpsichord with soft and loud"). Variations in volume (loudness) are produced in response to the pianist's touch (pressure on the keys): the greater the pressure, the greater the force of the hammer hitting the strings and the louder the sound produced and the stronger the attack. Invented in 1700, the fortepiano was the second keyboard instrument (in addition to the clavichord which predates it) to allow gradations of volume and tone according to how forcefully or softly the player presses or strikes the keys, unlike the pipe organ and harpsichord.

The invention of the piano is credited to Bartolomeo Cristofori of Padua, Italy, who was employed by Ferdinando de' Medici, Grand Prince of Tuscany, as the Keeper of the Instruments. Cristofori was an expert harpsichord maker and was well acquainted with the body of knowledge on stringed keyboard instruments. This knowledge of keyboard mechanisms and actions helped him to develop the first pianos. It is not known when Cristofori first built a piano. An inventory made by his employers, the Medici family, indicates the existence of a piano by 1700. The three Cristofori pianos that survive today date from the 1720s. Cristofori named the instrument un cimbalo di cipresso di piano e forte ("a keyboard of cypress with soft and loud"), abbreviated over time as pianoforte, fortepiano, and later reduced to only piano.