: likely refers to the release group or source quality (e.g., a "Studio" master or a specific encoder's tag).
: To watch the movie, you generally need all parts (01 through whenever it ends) in the same folder. Commando.1985Studio.part06.rar
: Large videos are often broken into smaller pieces (Part 1, Part 2, etc.) to make them easier to upload or download. : likely refers to the release group or source quality (e