Which group includes the piano?

• A. Strings
• B. Woodwinds
• C. Keyboard instruments
• D. Brass

Answer: (C)

The key idea is how the instrument is played and how its sound is produced. The piano is designed around a keyboard, and pressing a key moves a mechanism that makes hammers strike strings inside the instrument. The sound comes from those vibrating strings, but the way you interact with the instrument is through the keyboard, which is why it belongs with keyboard instruments.

In contrast, instruments in the strings family generate sound from vibrating strings that are bowed or plucked (or struck in some cases). The piano isn’t classified by the strings themselves, but by the interface you use to produce the sound. Woodwinds create sound with vibrating air produced by a reed or edge-blown mouthpiece, not by a keyboard-driven hammer mechanism. Brass instruments produce sound from buzzing lips on a mouthpiece. So the piano sits with keyboard instruments, not the other families. Keyboard instruments also include things like organs and harpsichords, which share the keyboard interface even though their sound production differs.