MOD video can be viewed on a computer with a player that is capable of reproducing MPEG-2 video. This video can be easily authored for watching on a DVD player without recompression, because it is fully compliant with DVD-video standard.
PVF is a special low-bandwidth ADPCM-based digital audio format for recording and storing human speech. A .pvf file contains digitally recorded speech in the PVF format. Such .pvf files were mainly used with legacy voice modems and software-based answering machines. Often, to be used with a specific modem, a .pvf file would have to be converted into the device-specific RMD format. Currently, PVF audio files can still be played with several major media players as well as converted into other formats (like WAV) with multi-format converter tools.