Science fiction (also known as sci-fi) is a film genre that makes use of speculative, fictional science-based depictions of phenomena that are not fully accepted by mainstream science, such as extraterrestrial lifeforms, spacecraft, robots, cyborgs, interstellar travel, and other technologies, to entertain audiences. Political and social themes have often been addressed in science fiction films, and philosophical topics such as the human condition have been explored in these films.
Using trick photographic effects, Georges Melies' A Trip to the Moon (1902) introduced the genre to the world during the early days of silent film. Next, there came Metropolis, which was the first picture in the genre to be released in full-length (1927). When it came to B movies, they were mostly low-budget productions from the 1930s through the 1950s. Because to Stanley Kubrick's groundbreaking science fiction film 2001: A Space Odyssey (1968), the genre of science fiction cinema was elevated in importance. Immediately after the success of Star Wars (1977), high-budget science fiction films with elaborate visual effects gained popularity among moviegoers, paving the stage for successive decades of blockbuster success.
Science fiction films are one of eleven super-genres identified by screenwriter and academic Eric R. Williams in his screenwriters' taxonomy, according to which all feature-length narrative films may be classed by these super-genres. The remaining 10 super-genres are as follows: action, crime, fantasy, horror, romance, slice of life, sports, thriller, war, and western.