Pedal explanation:

the right pedal is a sustain pedal, it lifts the dampers (which are not a part of the action) to allow the strings to continue to vibrate after the key is released. The middle pedal can vary in it's function, on most pianos it is a sostenuto, which while holding down a key or multiple keys then pressing the pedal will sustain those notes. Some pianos the middle pedal raises all the bass dampers, and a few pianos do not have a middle pedal. The left pedal is a soft pedal, it shifts the action to the right just enough so that the hammers strike only 2 strings rather than 3 allowing for a softer sound without playing the key any different.