What exactly does it mean when you burn as a UDF?

Okies I need a quick refresh… my best memory is that UDF is universal document format which was origionally desigened as packet writing standed back in windows 98. There were at the time a few different standards and you actually needed the proper UDF reader for your machine to figure out what the hell you actually burned on the disc. Fast forward to 2004 wtf does it mean when I tell nero or whatevre to burn a cd as a UDF file? Is there an actually UDF standard now? I know mount rainier is essentially a UDF format but I thought it was on the outs till the next windows?

Also what is the difference between the bunring system ie : SAO RAW DAO RAW etc?

… and is it just me or does nero not know wtf to do with an ISO. To change most of the options you need to break the ISO and rebuild it with nero? is that kinda wonky or did I miss something.

Oh i posted it here cause the liteon guys seem to be pretty up on stuff and post back if this post is supposed to be moved feel free to jack it mods.