Piano pedals are foot-operated levers at the base of a piano which change the instrument's sound in various ways. Modern pianos usually have three pedals. You can further modify the sound that you produce by using one of a piano’s two to three pedals. The soft pedal (una corda) on the left will make the sound quieter, while the damper pedal on the right will lift the dampers off all the strings
, allowing the strings to continue vibrating even when you have released the keys. There may be a middle pedal called the sostenuto pedal that works like the damper pedal, except that it only keeps one damper raised—the one that was raised at the moment the pedal was pressed. Or, the middle pedal may be a practice pedal instead, which will mute the sound by dropping a strip of felt in between the hammer and keys.
The development of the piano's pedals is an evolution that began from the very earliest days of the piano, and continued through the late nineteenth century. Throughout the years, the piano had as few as one modifying stop, and as many as six or more, before finally arriving at its current configuration of three.