There's a lot about Batman that's iconic, the costume, the gadgets, the Batcave and of course, the brooding. With so many points that are integral to his character, it's hard to imagine that any of them could be changed.
However, comics are a collaborative process and hundreds of costumes and concepts can get bounced around the office and a character can end up completely different from what was originally intended. Some of these ideas can be pretty out there and have led to some crazy things that have almost happened to the Dark Knight, from weird early designs to huge changes to existing characters.
Of course, that's just comics. The Dark Knight's transition to the big screen has also left behind a mountain of unused ideas. Creating a film is a long and complex process involving dozens or even hundreds of people. It's no surprise then that the end result can often end up completely different to what was originally planned.
It's a fascinating experience to look at the versions of Batman we could have got. These plans might have been good or bad, but either way it's like glimpsing into an alternate universe where one of the most recognisable heroes in the world is completely different.