What do the terms "damper," "sostenuto," and "una corda" refer to in relation to a piano?

In relation to a piano, the terms "damper," "sostenuto," and "una corda" refer to different pedals that control the sound and resonance of the instrument. The damper pedal sustains the sound by lifting all the dampers off the strings, the sostenuto pedal sustains specific notes, and the una corda pedal shifts the hammers to strike fewer strings, creating a softer sound.