Piano

The piano (in older Greek 'klidokymvalo') is a keyboard instrument; some consider it a string instrument, others a percussion instrument. After the church organ, it is the largest musical instrument. It is played with keys arranged horizontally: when the pianist presses a key, it raises a hammer that strikes the strings and produces the sound. The piano was invented by the Italian Bartolomeo Cristofori.

Because each key gives a different note, and each note can be played softly or loudly, the piano has an amazing range of expression. It can play alone or with an orchestra. Many think of it mainly as a classical instrument, but it plays a very important role in jazz, blues, rock and roll and popular music, either leading or accompanying other instruments.

There are two main types: upright pianos, whose strings run vertically, and grand pianos, whose strings run horizontally. Grand pianos are the best and also the most expensive, large not only in size but also in sound. Upright pianos are more common, because they take up less space and cost less.

The piano takes its name from the Italian 'piano', which in music means softly. The first piano, called the pianoforte or fortepiano (soft-loud), was invented around 1700 by Bartolomeo Cristofori. Its ancestors were the clavichord and the harpsichord.

It has a range of 7⅓ octaves and 88 keys, although some Bösendorfer models reach 8 octaves. Both types consist of a soundboard, case, frame, strings, keyboard, pedals and action. A piano usually has 52 white keys (of ivory or white plastic) and 36 black keys (of ebony or black plastic).

When a key is pressed, a felt-covered hammer strikes the string and falls back. The piano also has two or three pedals at the bottom. The left one is the una corda ('one string'): on an upright it moves the hammers closer to the strings for a softer sound, and on a grand it shifts the hammers sideways so that they strike fewer strings, again making the sound softer. The right one, the sustain pedal, lifts the dampers off the strings so that the notes ring on.

Most piano music is written for the piano alone, but many works combine the piano with a symphony orchestra, either as the solo instrument (piano concertos) or as one of the orchestra's instruments.