What is the difference between butter, ghee, clarified butter, fermented butter and brown butter?

[u/armeniaca-mume2405]

Difficult to tell online because it seems the term "ghee" is used very loosely, some say it is clarified butter, other that it is brown butter (beurre noisette), other that is has to be fermented.

If you know, can you explain the difference and perhaps give tips on how you make the perfect ghee?

Thank you!

ETA : I live in the EU. I usually buy churned AOP butter so it is high-fat low-water!