The piano is an acoustic, stringed musical instrument invented around the year 1700, in which the strings are struck by hammers. A piano has a row of 88 keys (52 white keys and 36 black keys). The white keys are for the C major scale (C, D, E, F, G, A and B). With the shorter black keys, the piano can play 88 different notes or pitches.

There are two main types of pianos: the grand piano and the upright piano. The grand piano is used for classical music solos, chamber music and is often used in jazz and pop concerts. The upright piano is more popular for private homes.

The original Sachs-Hornbostel system classified instruments into four main groups:

1) Idiophones, such as the xylophone, which produce sound by vibrating themselves

2) Membranophones, such as drums or kazoos, which produce sound by a vibrating

membrane

3) Chordophones, such as the piano or cello, which produce sound by vibrating strings

4) Aerophones, such as the pipe organ or oboe, which produce sound by vibrating columns of air. This category also includes the traditional brass instruments, such as the trumpet.

Later Sachs added a fifth category: electrophones, such as the electric guitar or electric bass, which produce sound through electricity and is required to be plugged in to an amplifier.

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