Science fiction is a genre of literature that is very hard to define because it varies drastically in themes. Some of these themes can include the search for immortality, travel in strange lands, encounters with unfamiliar creatures, trips beyond normal reality, and a superhuman hero's based on real science. However science fiction follows specific laws of physics, math and technology. The story often takes place in a real and viable way, in a world that is not yet reality. Science fiction is how the world one day may look and most of the time it is the worse case scenario, where technology plays an important role in society. However, it cannot take place in an alternative world, where magic often is an important. If it does it is considered fantasy. Science fiction stories are fictional stories with scientific theories that explains known phenomenon or predicts new phenomenon.
The first "real" science fiction novel is considered to be Mary Wollstonecraft's "Frankenstein" written in 1818. The story is established on the science of that age and many events were given explanations using a scientific approach. Authors that are seen as pioneers of science fiction are Robert Louis Stevenson "The Strange Case of Dr. Jekyll and Mr. Hyde" and Edgar Allan Poe. Edgar Allan.
Poe is mostly famous for his many tales or horror, but many of his stories are very close to science fiction. The authors that write science fiction as it is known today are Jules Verne, among his most famous books are "Journey to the Centre of the Earth" written in.
1864 and "From the Earth to the Moon" written in 1873 and H.G. Wells, "The Time Machine: an invention" written in 1895 and "The War of the Worlds" written in 1898.
The start of science fiction as a genre of its own, presumably took place in 1926 when the magazine "Amazing Stories" was first published. The editor was the journalist and publisher Hugo Gernsback, who labelled this kind of stories "scientification".