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Speculative fiction

Speculative fiction, a broad genre that spans fantasy, science fiction, and horror by exploring worlds that cannot exist under the known physical laws or current technologies. It covers themes in the context of supernatural, futuristic, and other imaginative realms, deals with human experience rather than technology, and explores possible futures. The genre also includes hybrids, derivatives, and related subgenres such as gothic, dystopian, weird fiction, post-apocalyptic fiction, ghost stories, superhero tales, alternate history, steampunk, slipstream, magical realism, and fractured fairy tales.

While science fiction speculates on future events with a foundation in scientific principles, fantasy and paranormal stories introduce elements of the supernatural, with paranormal fiction typically set in the real world. Dark fantasy is a type of horror in which humanity is threatened by forces beyond human understanding. The subgenre allows the narratives to shift from the viewpoint of the monster rather than the victim or survivor. 

The table below represents the most comprehensive summary I found:

Fantasy

Fiction that cannot or will never occur.

Classical Fantasy

Improbabilities explained by magic-type powers

High Fantasy

Elves, dragons, swords and sorcery

Mythic Fiction

Classic good vs evil; deities and superheroes.

Dark Fantasy

Gothic, horror, ghosts, vampires, werewolves

Science-Fiction

Improbabilities explained by improbable technology

Space Romance

Relationships-driven story with nominal, arguably unessential SF subplots.

Space Opera

Focus on a colorful cast of characters and dramatic or political conflicts rather than scientific plausibility.

Science Fiction

Fiction based on a projection of what may be possible using current knowledge.

Soft Sci-Fi

Otherwise possible world with one or more major departures from accepted science.

Social Sci-Fi

The impacts of major technological advances on humanity

Sci-Fi adventure

Opportunities afforded by technology with more scientific realism than Sci-Fi

Hard Sci-Fi

Fiction based upon projections using solid scientific principles and knowledge.

Applied theory

Fiction that uses known scientific principles to explore possible future advances, which are currently unattainable due to political, technological, or financial limitations.

Call to action

Shows probable future problems arising from likely advances in science.