If you are looking for the "paper" (documentation or information) regarding this specific file, it is typically an container, which supports multiple subtitles and audio tracks.
: A highly popular drama often uploaded with such request tags. prmoviesrequest ep 57.mkv
: A Turkish drama (dubbed) that has reached these episode numbers recently. If you are looking for the "paper" (documentation
: Another commonly requested dubbed series. it is typically an container