Steampunk is a style of fiction having to do with a semi-fictional world where old machinery from the Victorian 19th century is still being used. Technologies that were new or important to the Victorians, such as steam power, clockwork or electricity, are big themes in steampunk.

Important influences on steampunk are the Victorian "scientific romances", the first science fiction novels. Authors like Jules Verne and H.G. Wells are still very popular. Modern novels often cross-over with Goth and vampire themes.

The fictional style has become an active 'scene' where steampunks dress in costume and attend meetings or conventions. This costume is a large part of the scene. Many steampunks spend lots of time sewing their own outfits, or collecting accessories such as hats and goggles. The Maker movement involves many people who are both Makers and steampunks. They make Contraptions, fanciful devices as either art or a pretended function. Some of these contraptions are as large as cars, buses or even a steam-powered mobile house.

Sometimes this aspect is expanded to include cultural ideas of the 19th and early 20th century, such as small items like clothing and accessories, or large objects such as locomotives (trains) or machines that have not even been invented yet, like airplanes.

Steampunk themes in fiction 
Sometimes steampunk is used in stories to give a rough, gritty feel. This is typical of American steampunk stories, where many stories are set around the Old West or the American Civil War. 

British steampunk is a contrast to this. Instead it considers Victorian society as a more polite society and tries to re-create a world of politeness, etiquette and distinctions between classes.

Neither flavour of steampunk cares too much about historical accuracy. The purpose is to have fun, not to accurately re-enact a period of real history.

Favourite Steampunk machines 
Steampunks are very fond of particular machines and these keep re-appearing as themes in fiction or in costume.
 Time machines
 Zeppelins and airships
 Ray guns
 Robots, especially robots that walk on legs.

Costume 
 Goggles
 Goggles are one of the most popular pieces of steampunk costume. Part of "the story" for steampunks is their bravery in hazardous situations, either exploring remote and dangerous places, or experimenting in their laboratory. In both of these, goggles are essential protective equipment.  Steampunk goggles often have telescopic lenses or swivelling lenses on posts that can be rotated in front of the eyes.
 Hats
 Hats are not often worn today, compared to the past, and so steampunks favour wearing them as an easy and distinctive piece of costume. Favourite hat styles are top hats, pith helmets and pickelhaubes.
 Boots
 Gloves
 These range from ordinary gloves with gears and other accessories sewn on to give them a more technical appearance all the way to highly detailed mechanical hands.
 Ray guns
 Ray guns with ornate gearwork or tubing are popular.
 Accessories
 Victorian era accessories such as pocket watches, brass spyglasses, or walking sticks are also popular components of steampunk costumes.  Some outfits include large tanks worn on the back.

 For ladies 
 Corsets
 Female steampunk fans sometimes wear corsets on the outsides of their costumes, contrary to actual Victorian era fashions.
 Bustles
 Jewelry
 Steampunk jewelry typically includes gears.  The octopus is a popular theme, perhaps inspired by the attack of the cuttlefish on the Nautilus in the Jules Verne story 20,000 Leagues Under the Sea.

Origins of the name 
The word "steampunk" is made of the root words "steam" and "punk".

A well-known science-fiction author William Gibson, wrote books in the early 1980s that created the "cyberpunk" style. Later he, and the writer Bruce Sterling, wrote one of the early steampunk novels The Difference Engine. This book was popular and readers looked for a term to describe this new style. They chose "steampunk", from "steam" and "cyberpunk".

An alternate story is that the term was coined by writer K.W. Jeter in a letter to Faren Miller at Locus magazine.

Derivative styles 
There are several related styles that have grown from steampunk. These usually have names ending in "-punk". The best known is "Dieselpunk", which is set in the 1930s. Like the Steampunk fondness for Victorian steam machines, Dieselpunks like the Modernist style of the 1930s, with polished aluminium aircraft and petrol or diesel engines.

Another variety is set in the American frontier during the late 19th century.  The American 1960s television series Wild Wild West is a good example of this.

Paranormal steampunk includes legendary creatures such as werewolves or vampires and mixes horror with steampunk.

Works of fiction based in or on Steampunk

Books
The Oswald Bastable (Nomad of the Time Streams) series by Michael Moorcock
Morlock Night by K.W. Jeter
Time Ships by Stephen Baxter
The time machine by H. G. Wells

Video and Computer games
Riven- based heavily in the use of metal, steam-powered or manual, mechanical devices.
Myst III: Exile- Two worlds in the game are based in steampunk mechanics; one based heavily on steam and water power, and the other on manual mechanics.
Myst IV: Revelation- The main hub location of the game, Tomahna, partially involves the use of mechanical and electrically-powered devices. However, some items in the game are anachronistic (they do not exactly belong in that time period), such as cathode ray tubes (basic TV screens) and circuit boards. The clothing worn by the characters in the game are also similar to 18th and 19th century clothes.

Film
First Men in the Moon (1964) - Based on a story by H.G. Wells.
Journey to the Center of the Earth (1959) - Based on a story by Jules Verne.
The League of Extraordinary Gentlemen (2003) - Based on (but differs greatly from) a graphic novel by Alan Moore.
Sky Captain and the World of Tomorrow (2004) - A dieselpunk film.
Steam Trek  (1994) - Is a parody of Star Trek done as a steampunk film.
Wild Wild West - a 1960s television series.
Wild Wild West (1998 film)- an adaptation of the original 1960s television program.
Steamboy

References

Other websites

Brass Goggles, the Steampunk Forum 

Fiction genres