Batman is so popular that even people who don't religiously follow his comics know the most important parts of his lore. Batman was Bruce Wayne, he was Gotham City's dark protector, he fought villains like The Joker, and so forth. However, DC Comics either forgot about many aspects of Batman's lore that DC Comics or deliberately buried them.
Source：https://www.cbr.com/batman-lore-stories-need-return-dc-comics/
