Science fiction film is a film genre that uses science fiction: speculative, science-based depictions of phenomena that are not necessarily accepted by mainstream science, such as extraterrestrial life forms, alien worlds, extrasensory perception, and time travel, often along with futuristic elements such as spacecraft, robots, cyborgs, interstellar space travel or other technologies. Science fiction films have often been used to focus on political or social issues, and to explore philosophical issues like the human condition. In many cases, tropes derived from written science fiction may be used by filmmakers ignorant of or at best indifferent to the standards of scientific plausibility and plot logic to which written science fiction is traditionally held.
The genre has existed since the early years of silent cinema, when Georges Melies' A Trip to the Moon (1902) amazed audiences with its trick photography effects. The next major example in the genre was the 1927 film Metropolis. From the 1930s to the 1950s, the genre consisted mainly of low-budget B-movies. After Stanley Kubrick's 1968 landmark 2001: A Space Odyssey, the science fiction film genre was taken more seriously. In the late 1970s, big-budget science fiction films filled with special effects became popular with audiences after the success of Star Wars and paved the way for the blockbuster hits of subsequent decades.
Robots have been a part of science fiction since the Czech playwright Karel Čapek coined the word in 1921. In early films, robots were usually played by a human actor in a boxy metal suit, as in The Phantom Empire, although the female robot in Metropolis is an exception. The first depiction of a sophisticated robot in a United States film was in The Day the Earth Stood Still.
Robots in films are often sentient and sometimes sentimental, and they have filled a range of roles in science fiction films. Robots have been supporting characters, such as Robby the Robot in Forbidden Planet, sidekicks (e.g., C-3PO and R2-D2 from Star Wars), and extras, visible in the background to create a futuristic setting. As well, robots have been formidable movie villains or monsters (e.g., the robot Box in the 1976 film Logan's Run. In some cases, robots have even been the leading characters in science fiction films; in the 1982 film Blade Runner, many of the characters are bioengineered android "replicants".
Films like Bicentennial Man and A.I. Artificial Intelligence depicted the emotional fallouts of robots that are self aware.
One popular theme in science fiction film is whether robots will someday replace humans, a question raised in the film adaptation of Isaac Asimov's I, Robot, or whether intelligent robots could develop a conscience and a motivation to take over or destroy the human race (as depicted in The Terminator).
