Percussion instruments are any type of object whose sound is not produced by strings, a reed or blown. Therefore, anything that is tapped, hit, dropped, rattled, scraped etc. would be a percussion instrument.
The list of percussion instruments is therefore endless, but here are some typical orchestral percussion instruments:
*Pitched percussion or definite pitch. These are instruments which can be tuned to specific notes or pitches.
*Unpitched percussion or indefinite pitch. These are instruments which cannot be tuned to a specific note or pitch.