What are pedals for on a piano and how do they affect the sound produced by the instrument?

Pedals on a piano are used to sustain, soften, or change the tone of the notes being played. The sustain pedal allows the notes to ring out longer, the soft pedal reduces the volume and changes the tone to a softer sound, and the una corda pedal shifts the hammers to strike fewer strings, creating a quieter and more delicate sound.