Science Fiction
Science fiction is a genre of literature, film, theater, and other forms of expression focusing on fantastic or futuristic worlds. The term 'science' is misleading, as often the story takes place in an unadvanced era, similar to that of the Middle Ages, and may involve magic.
The Science fiction genre includes hard science, which is based on accurately portraying the real world, or fiction that uses alternate science which is invented to advance the plot of the story. In this invented science genre the author needs to explain the science at some point so the reader can appreciate its use in the story. Science fiction may also include the Fantasy genre, where majic and fairies may reside.
Notable Science Fiction Series
Discworld - Terry Pratchett
The Foundation series - Isaac Asimov