In modern popular fiction, a superhero (sometimes rendered super-hero or super hero) is a type of costumed heroic character who possesses supernatural or superhuman powers and who is dedicated to fighting crime, protecting the public, and usually battling supervillains. A female superhero is sometimes called a superheroine (also rendered super-heroine or super heroine). Fiction centered on such characters, especially in American comic books since the 1930s, is known as superhero fiction.
By most definitions, characters do not require actual supernatural or superhuman powers or phenomena to be deemed superheroes. While the Dictionary.com definition of "superhero" is "a figure, especially in a comic strip or cartoon, endowed with superhuman powers and usually portrayed as fighting evil or crime", the longstanding Merriam-Webster dictionary gives the definition as "a fictional hero having extraordinary or superhuman powers; also: an exceptionally skillful or successful person". Terms such as masked crime fighters, costumed adventurers or masked vigilantes are sometimes used to refer to characters such as the Spirit, who may not be explicitly referred to as superheroes but nevertheless share similar traits.
Some superheroes use their powers to counter day-to-day crime while also combating threats against humanity from supervillains, who are their criminal counterparts. Often at least one of these supervillains will be the superhero's archenemy. Some long-running superheroes such as Iron Man, Captain America, Superman, Wonder Woman, Batman, and Spider-Man have a rogues gallery of many villains.