A piano (also called a pianoforte) is a musical instrument classified as a percussion instrument that is played by pressing keys on a keyboard. Each key is a lever that makes a hammer inside the piano hit a string inside, producing a sound. Each string has a different length and so produces-a different note.

The piano has been an extremely popular instrument in Western classical music since the late 18th century. A person who plays the piano is called a pianist.

(source: https://simple.wikipedia.org/wiki/Piano)