Steampunk is a Subgenre of fantasy & Speculative Fiction which came into prominence in the 1980s and early 1990s. In other word , Its a genre of science fiction set in Victorian times when steam was the main source of machine power.
Steampunk is often related with cyberpunk and shares a similar fanbase and theme of rebellion, but developed as a separate movement.
Recent Steampunk :William Gibson and Bruce Sterling's 1990 novel The Difference Engine is often credit.This novel applies the principles of Gibson and Sterling's cyberpunk writings to an alternate Victorian era where Charles Babbage's proposed steam-powered mechanical computer, which he called a difference engine (a later, more general-purpose version was known as an analytical engine), was actually built, and led to the dawn of the information age more than a century ahead of scheduled as bringing widespread awareness of the genre "steampunk" among science fiction fans.
http://en.wikipedia.org/wiki/Steampunk#Recent_steampunkWilliam Ford Gibson (born 3 March 1948) is an American-Canadian writer who has been called the "noir prophet" of the
cyberpunk subgenre of science fiction. with his novel Neuromancer (1984) is likely the most famous writer connected with the term cyberpunk.
Neuromancer almost the first cyberpunk videogame. The idea of cyberpunk itself is not common among games as of this writing, and author William Gibson is one of the most influential people shaping the genre. This particular title is based on Gibson's novel of the same name.
Early short fictionGibson's early writings are generally near-future stories about the influences of cybernetics and cyberspace (computer-simulated reality) technology on the human race.
Later 21st-century incarnationAfter All Tomorrow's Parties, Gibson began to adopt a more realist style of writing, with continuous narratives – "speculative fiction of the very recent past." SF critic John Clute has interpreted this approach as Gibson's recognition that traditional science fiction is no longer possible "in a world lacking coherent 'nows' to continue from", characterizing it as "SF for the new century". Gibson's novels Pattern Recognition (2003) and Spook Country (2007) were both set in the same contemporary universe –"more or less the same one we live in now"- and put Gibson's work onto mainstream bestseller lists for the first time. As well as the setting, the novels share some of the same characters, including Hubertus Bigend and Pamela Mainwaring – employees of the enigmatic marketing company Blue Ant.
Cyberpunkphase of American science fiction in the 1980s and 1990s most often associated with William Gibson's novel Neuromancer (1984). It's breifly written down to assist the memory or for future reference that it focus on "high tech and low life". Cyberpunk fiction is influenced by the gloomier world of hard‐boiled detective fiction and by film noir thrillers.
Cyberpunk plots often center on a disagreement among hackers, artificial intelligences, and mega corporations. They dispose to be set in a near-future Earth, rather than the far future settings or galactic vistas found in novels like Isaac Asimovs Foundation or Frank Herbert's Dune.
Berlin's Sony Center reflects the global reach of a Japanese corporation. Cyberpunk is often set in urbanized, artificial landscapes, and "city lights at night" was one of the genre's first metaphors for cyberspace (
Neuromancer).
Crystal
Steampunk is a term set in an era or world where steam power was still widely used—usually the 19th century, and often set in Victorian era England—but with prominent elements of either science fiction or fantasy, such as fictional technological inventions, or real technological developments like the computer occurring at an earlier date. It is a subgenre of fantasy and speculative fiction which came into prominence in the 1980s and early 1990s. 
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