A superhero or superheroine is a stock character who typically possesses superpowers or abilities beyond those of ordinary people, is frequently costumed concealing their identity, and fits the role of the hero; typically using their powers to help the world become a better place, or dedicating themselves to protecting the public and fighting crime. Superhero fiction is the genre of fiction that is centered on such characters, especially, since the 1930s, in American comic books, as well as in Japanese media.

Superhero fiction is a subgenre of speculative fiction examining the adventures, personalities and ethics of costumed crime fighters known as superheroes, who often possess superhuman powers and battle similarly powered criminals known as supervillains. The genre primarily falls between hard fantasy and soft science fiction in the spectrum of scientific realism. It is most commonly associated with American comic books, though it has expanded into other media through adaptations and original works.