from the man page, it said it is a configuration file for modprobe/insmod which I can understand.

What I don't understand is those alias stuff like char-major-20-175, what has it anything to do with module ? who is going to modprobe it in this form ? I see reference to these alias often especially the sound stuff.

I thought it is more like devices than module then why put it here ?

Would appreciate someone can give me a clue, thanks in advance.