What's the deal with .nfo files

Maybe this is a silly question, but what is the file sharing obsession with .nfo files? I don't get it at all. I mean, by default double clicking them results in some weird system property box coming up in windows, so you have to open them in notepad. So, if you've got to do that, why not use just a plain text file?

I've never come across them anywhere else, either, really, except filesharing. Maybe they do all sorts of things that I'm not aware of, but I was thinking about this the other day, and I really don't get why you always seem to get one packaged in with your download on bit torrent for example, or rared in on emule. Wouldn't a .txt file be simpler?

nfo files use extended ascii and have weblinks that notepad doesn't support (very well)
so get "DAMN NFO reader" and never have that problem again.

Or another freeware program: Download Getdiz