An English Other typically refers to a person who has a profession apart from media but has also contributed to either movies or TV in some or the other manner. Their contribution to the media industry could have been by way of a voice over artist, playing small roles, providing music etc.
This includes people who are passionate towards media but can not take up a media related job for their living. These people may have played small characters in a movie or a TV Series, composed music albums, dubbed for certain people or even played a cameo. They try and connect with the people as much as possible and make sure that their presence in any movie or program or series is worth the audience's time.
Their role is minimal yet makes a huge difference in the completion of a film, for a movie lives in its little details.