Every acoustic piano, whether a glossy concert grand or a well-worn upright, part of an orchestra or a jazz combo, shares certain characteristics with every other piano:
Keyboard: The keyboard is what makes a piano a piano. On an acoustic piano, the keyboard is comprised of 88 black and white keys. The keys are what you press or strike, tap or pound to produce that inimitable piano sound.
Housing and lid: Whatever shape a piano takes — the curves of a grand or the rectangle of an upright, your piano also has a lid. Propping open the lid on a grand piano gives you a louder and more resonant sound than when the lid is down. Opening the lid of an upright doesn’t do as much for your sound as pulling the piano away from the wall does.
Pedals: Pedals — sometimes two, but generally three — are part of a piano as well. With the pedals you can make the sound softer or make certain notes sound longer.
Keys, hammers, and strings: These parts actually produce the sound. Each of the 88 keys is connected to a small, felt-covered hammer. When you press a key, its hammer strikes a string, or set of strings, tuned to the appropriate musical note. The string begins to vibrate extremely rapidly. Your ear picks up these vibrations, and you hear music. The entire vibration process occurs in a split second.
To stop the strings from vibrating, another mechanism called a damper sits over the strings inside the keyboard. Dampers are made of cloth or felt that mutes the strings by preventing any vibration. When you press a key, in addition to triggering the mechanism that vibrates the string, a piano key also lifts the damper. When you release the key (provided you’re not holding down a pedal), the damper returns to mute the string so that all your notes don’t crash into each other.
Hammers vibrate piano strings to produce music to your ears.