The language of the audio or the specific regional version of the content. S01E01: Season 1, Episode 1.
This indicates that "English Subtitles" are included (hardcoded or muxed into the file). .mkv: The file container (Matroska Video).
The source website or the "tag" of the group that encoded and uploaded the file. 720p: The resolution (High Definition).
Likely a unique release ID or internal code for the uploader/group.
This version contains scenes that may have been cut from the original theatrical or broadcast version.
The video codec used (High Efficiency Video Coding). This means the file is compressed to be small without losing much quality.
This filename follows a standard format used by online media release groups.
The source of the video was a high-definition digital stream or file.