Steampunk is science fiction that's set in the 1800s and features the steam-powered technology of that era.
Steampunk books, movies, and graphic novels imagine a futuristic world with elements of 19th century fashion and technology. Some steampunk machines, vehicles, and fashions seem like they were imagined in the 1800s. The word was coined in the late 1980s, modeled on cyberpunk, with steam referring to Victorian era steam engines. A steampunk outfit could include a long skirt and petticoat worn with brass goggles, or a vest, top hat, and pocket watch.