Older pianos often have fewer keys. How to play When you press one of the piano's keys, it causes a felt hammer to hit the tuned strings inside the instrument. The strings vibrate to create a sound.

The curtain was cut into a fringe in the same spacing as the hammers – marking the hammer ... hit the strings with the metal clips rather than their soft felt heads. It makes the piano sound ...

You can see here the hammer is hitting really thick strings. So that is a pianoand you play a piano with keys. But what about otherstring instruments? A guitar works by either pluckingthe strings ...