Science fiction

Science fiction (often shortened to sci-fi or scifi) is a genre of speculative fiction, typically dealing with imaginative concepts such as futuristic science and technology, space travel, time travel, faster than light travel, parallel universes, and extraterrestrial life. Science fiction often explores the potential consequences of scientific and other innovations, and has been called a "literature of ideas." It usually avoids the supernatural, and unlike the related genre of fantasy, historically science fiction stories were intended to have a grounding in science-based fact or theory at the time the story was created, but this connection is now limited to hard science fiction.

Science fiction is difficult to define, as it includes a wide range of subgenres and themes. Author and editor Damon Knight summed up the difficulty, saying "science fiction is what we point to when we say it", a definition echoed by author Mark C. Glassy, who argues that the definition of science fiction is like the definition of pornography: you do not know what it is, but you know it when you see it.

Hugo Gernsback, who was one of the first in using the term "science fiction", described his vision of the genre: "By 'scientifiction' I mean the Jules Verne, H. G. Wells and Edgar Allan Poe type of story—a charming romance intermingled with scientific fact and prophetic vision."

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