The piano uses wooden hammers padded with felt to hit the strings. The harder the pianist presses a key, the harder the hammer hits the strings and therefore the louder the sound that is made. In this way, many notes can be played at once. It also has pedals to produce different effects - sustaining the notes or dampening them.
Pianos are built in many shapes and sizes. In grand pianos (the largest), the strings are horizontal, whereas in an upright piano, they are vertical.
Famous composers who wrote many pieces for the piano include Mozart, Beethoven, Chopin, Liszt and Debussy.
