This is a list of stock characters that are used in science fiction. * Absent-minded professor such as Emmett Brown in Back to the Future * Alien * Alien invader * Android * Bug-eyed monster * Child * Clone * Computer * Cyborg * Demon * Disabled people in hi-tech wheelchairs or with prosthetics * Doctor especially in Star Trek. * Esper * God * Golem * Hero * Hitler * Hive-mind * Journalist * Little green men * Lotus-eaters * Machine * Mad Scientist—an early example is Socrates in Aristophanes' The Clouds. * Martian * Messiah * Monster * Mutant * Robot * Scientist * Sex object * Shapeshifter * Superhero * Superman * Supernatural creature * Villain * Z