What are the four percussion instruments?

The four main categories of percussion instruments are:

1. Idiophones: These instruments produce sound through the vibration of their entire body. Examples include xylophones, marimbas, gongs, and bells.

2. Membranophones: These instruments produce sound through the vibration of a stretched membrane. Examples include drums, timpani, and bongos.

3. Chordophones: These instruments produce sound through the vibration of strings. Examples include guitars, violins, and pianos.

4. Electrophones: These instruments produce sound through the conversion of electrical signals into sound waves. Examples include synthesizers, drum machines, and theremins.