The original Hornbostel/Sachs system had 4 categories:
1. Idiophones - Instruments that vibrate themselves such as a xylophone
2. Membranophones - Instruments that have a vibrating membrane such a as a drum.
3. Chordophones - Instruments with vibrating strings
4. Aerophones - Instruments which incorporate vibration of air.
They will both have the same color streak.
Do you mean biography?
If so, it’s important because it shows the lives and backgrounds of creators, famous or not, of things in the arts.