1923.s01e01.1080p.amzn.webrip.opus.av1-nash.mkv -

The name of the release group or individual who encoded and uploaded the file.

Season 1, Episode 1 (the series premiere titled "1923"). 1923.S01E01.1080p.AMZN.WEBRip.OPUS.AV1-NASH.mkv

The video was captured/recorded from a streaming service rather than a direct digital download (WEB-DL) or a physical disc. The name of the release group or individual