Hard-of-hearing or localized subtitles can be embedded or toggled on and off without degrading the video quality.

This points directly to the originating website, release group, or community forum (typically a domain like pikahd.com or similar) that encoded or first hosted the file. Release groups put their stamp on files to build reputation within sharing communities.

—all refer to specific file naming conventions and sources used in the online anime community, particularly for dual-audio releases in Hindi and English.