What are three names of the piano pedals?

The far left pedal on some pianos when pressed, will sustain the lower half of the piano. This ideal for holding down a chord for a long time or when both hands are needed higher up on the piano. It's rarely used. However on some pianos, it's used to lightly soften the sound of the piano.

The middle pedal is the practice pedal. It dramatically softens the sound of the piano.

The far right pedal is the sustain pedal. It lifts the dampers on the piano so that every note that is hit, keeps ringing until the pedal is released, dropping the dampers and stopping the sound.

A side note to this is that the functions of each pedal varies from piano to piano, although, the far right sustain pedal is the same on ever piano.