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 extra-terrestrial life forms, alien worlds, ESP, and time travel, often along with futuristic elements such as spacecraft, robots, 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 and paved the way for the blockbuster hits of subsequent decades. 10. RoboCop (1987) - Paul Verhoeven 09. Minority Report (2002) - Steven Spielberg 08. Invasion Of The Body Snatchers (1956) - Don Siegel 07. Back To The Future (1985) - Robert Zemeckis 06. Dark City (1998) - Alex Proyas 05. Solaris (1972) - Andrei Tarkovsky 04. Metropolis (1927) - Fritz Lang 03. Star Wars (1977) - George Lucas 02. Blade Runner (1982) - Ridley Scott 01. 2001: A Space Odyssey (1968) - Stanley Kubrick