The Matroska Multimedia Container format, which supports multiple audio and subtitle tracks in one file.
The video compression standard (H.264/MPEG-4 AVC) used to create the file. Operation.Seawolf.2022.PL.BDRip.x264-K83.mkv
The "tag" or name of the release group that encoded and distributed this specific file. The Matroska Multimedia Container format