I was very surprised that I couldn't find this answer on Google.
I have seen someone access the default Apache index page (no index.html present, so it just shows the directory listing) with query string parameters. The URL they used was similar to:
http://example.com/?C=M;O=D
It looks like O=D
means "order = descending," since it reversed the order of the list, but I want to know what other parameters can be passed in, and what they mean. Is this documented somewhere? I couldn't find it.