
1) Windows-only freeware
Found on
https://www.crosswordclues.com/clue/ratdvd

RatDVD (originally stylized `ratDVD`) is the name of a proprietary container format for digital video, developed by Peter Jensen and a group of Russian and Danish university students. The container format is a compressed archive format that holds all features of DVD-Video in a single file. Unlike other container formats like Matroska, it is desi.....
Found on
http://en.wikipedia.org/wiki/RatDVD
No exact match found.