Fansub

A fansub is a subtitle track made by viewers rather than a licensor. In the 1980s that meant overlaying text onto a VHS copy with a genlock and mailing the tape to strangers, with clubs running distribution trees so a series could spread without anyone selling anything. Quality varied wildly. So did the translation, since the people doing it were often learning Japanese as they went.

Digital tools changed the scale. By the early 2000s groups were ripping broadcasts, translating, timing, typesetting and encoding within a day or two, then releasing over BitTorrent. Karaoke effects on the opening became a signature. So did translation notes crowding the top of the frame to explain a pun, a food, or a word the group had decided to leave in Japanese on principle.

The scene mostly ran on an honour rule: stop distributing once a series is licensed in your language. Legal simulcasts eventually made the argument moot for new shows, and many groups shut down or moved to older titles nobody has picked up. What survives is the habit those tapes built, of a Western audience that expects to watch in Japanese.