The audio track language. In the P2P world, language tags were vital for regional users, especially in countries like Italy where localization and dubbing are culturally dominant.
The video codec used to compress the file. In 2009, XviD was the undisputed king of video compression for standard-definition playback. It allowed near-DVD quality files to be compressed down to roughly 700 megabytes (the capacity of a standard CD-R).
