We also noted that while powers are not required, heroes without powers use fight training, gadgets, and technology as a replacement. We concluded that while powers are not a necessity, some form of physical advantage is a necessity.
But if that's all it takes, then there are many hero characters who could be defined as superheroes but aren't. James Bond for example.
So, what is a superhero?
I have the answer, and it's shockingly simple:
A superhero is a person with some form of physical advantage against their enemies who publicly fights crime. That's the key! The part about fighting crime publicly. Even superheroes who lurk in the shadows have a public reputation.
Secret identities, costumes, powers... They're great additions to a character, but they don't define the hero.