Steampunk is different things to different people, so rather than trying to write an article on what it means to us, we're going to give you a few samples from people we believe said it best.
Steampunk is a sub-genre of science fiction and speculative fiction, frequently featuring elements of fantasy, that came into prominence in the 1980s and early 1990s. The term denotes works set in an era or world where steam power is still widely used — usually the 19th century, and often Victorian era England — but with prominent elements of either science fiction or fantasy, such as fictional technological inventions like those found in the works of H. G. Wells and Jules Verne, or real technological developments like the computer occurring at an earlier date.
--- Wikipedia article on Steampunk
H.G. Wells, Nikola Tesla, and Jules Verne are often considered to be among the founding fathers of Steampunk.
Steampunk simply embodies a time and a place. The time... the late 19th century. The place... a steam powered world, where air travel by fantastical dirigibles is as common as traveling by train or boat (or submarine). A place where national interests are vastly different than our own version of history. A place where the elegant and refined are as likely to get pulled into a grand adventure, as the workers, ruffians, and lower classes. A place where the idea of space travel is not so far fetched. A place where lost civilizations are found and lost again. A place where anything is possible, and science can be twisted to meet ones own ends. That to me is the essence of Steampunk. It can have political overtones and commentary, or it can be straight escapist fiction. Either way, if it meets these criteria. It is Steampunk.
--- Joshua A. Pfeiffer a.k.a. Vernian Process
