Dystopias are societies in cataclysmic decline, with characters who battle environmental ruin, technological control, and government oppression. Dystopian novels can challenge readers to think differently about current social and political climates.
Science fiction that features the use of technology, mainly weapons, for military purposes and usually principal characters that are members of a military organisation involved in military activity, usually during a war; occurring sometimes in outer space or on a different planet or planets.
Science fiction is a genre of speculative fiction that typically deals with imaginative and futuristic concepts such as advanced science and technology, space exploration, time travel, parallel universes, and extra-terrestrial life. Often explores the potential consequences of scientific, social, and technological innovations.
Science fiction that emphasises space warfare, melodramatic adventure, interplanetary battles, chivalric romance, and risk-taking. Set mainly or entirely in outer space, it usually involves conflict between opponents possessing advanced abilities, futuristic weapons, and other sophisticated technology.
Steampunk incorporates technology and aesthetic designs inspired by 19th-century industrial steam-powered machinery. Often set in an alternative history of the Victorian era or the American "Wild West", where steam power remains in mainstream use, or in a fantasy world that similarly employs steam power.
Time travel may form the central theme of a book or it can simply be a plot device to drive a story. The story may ignore the possible effects of the time traveller’s actions or it could exploit its repercussions.
Utopian fiction is a style of fiction that takes place in an idealised world. Generally about exploring real problems facing our world and making political, philosophical, or moral points through storytelling.