Some source cited from Wikipedia.org.
Project Educate: Steampunk:
Steampunk is a sub-genre of science fiction. It typically will feature steam powered vehicles not limited to trains, and is inspired by industrialized Western civilization during the 19th century. It may also convey traces of a dystopian or post-apocalyptic environment, and often contains elements of the Wild West.
Before we called it 'Steampunk', there were elements in books and movies. The oldest precursor is the film 'Metropolis', a 1927 German expressionist science-fiction directed by Fritz Lang.
The term we now call it originated in the late 1980's, a variant of cyberpunk. It wasn't until 1995, though, that something was actually titled using it, Paul Di Filippo's Steampunk Trilogy.
For a long time, the elements of steampunk were used mainly in literature. It was easier, and of course cheaper, to describe the giant cities, and steam based machinery then it would be to create it for the screen. There was a 1960's television show which featured many elements of advanced steam-powered technology set in the Wild West, but it was Dr.Who that really set things in to motion.
As we know it now, steampunk is a widely acknowledged genre of film and literary media, and it is cosplayed often. A key element in choosing a cosplay outfit is that you can become your character, and it doesn't need to exist in a game, movie or book for you to be realistic.
Using cogs, clocks, goggles, corsets, bomber jackets, tophats and modified weapons, anyone can come up with a believable and excellent cosplay with a little time and effort.
Some people say that in order to make a great Steampunk cosplay, though, you have to believe you are the character. It wouldn't make sense for you to have vials and potions if you wanted to be a pilot!
Steampunk Goggles Tutorials:
One thing almost every Steampunk cosplay needs is Goggles. Below are some excellent tutorials for you to try your hand at making this accessory.
Random Steampunk Bits n' Bobs:
Excellent Steampunk Cosplay:
Project Educate: Welcome to Cosplay Week!
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The A, B, C's of Cosplay 2 (D, E, F)
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The A, B, C's of Cosplay 2 (G, H, I)