it is defined as photography that records important events. There is something "historical and newsworthy" about the way the word is used. But I think it's a perfect definition of wedding photography.
Documentary wedding photography captures what happens without intervention or posing. There's no studio with lights and you're not asked to do it often.
You won't find many helpers hanging around either. And the "shooting" process is almost trivial. Tell the truth and most importantly tell the story as honestly and realistically as
possible.