Speculative fiction is a type of fiction that borrows some basic components from fantasy, horror and science fiction, but it differs in that it focuses on ideas and theories about worlds, people and situations that are not a part of everyday life. Some authors consider speculative fiction to actually be an umbrella term that covers all of the non-realistic fiction, since it can be broken down into many specific components. But one concrete idea about speculative fiction is that it definitely does not deal in reality. What's interesting about this type of writing is that it often takes concrete ideas and theories and creates speculative alternatives of them. Depending on the subject, this can result in highly interesting and sometimes highly controversial writings. The term "speculative fiction" was first coined sometime in the late 1800s; it has been used to describe books in a more mainstream way since the mid 1900s.
Speculative fiction has been around for a very long time. From the very beginning of the written word, you could find many authors dabbling in what would later be labeled as speculative fiction. Examples of this type of fiction include Harlan Ellison's writings, and Margaret Atwood's notorious book, "The Handmaid's Tale".
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