A subgenre of science fiction is a specific category that focuses on particular themes, settings, or styles within the broader genre. Examples include cyberpunk, which explores advanced technology and its impact on society, and space opera, characterized by epic adventures in outer space. Each subgenre often has its own conventions and tropes that distinguish it from others. Another notable subgenre is dystopian fiction, which presents a society characterized by oppression and control, often as a cautionary tale about current social issues. Time travel is also popular, allowing characters to move between different periods, raising questions about causality and history. These subgenres enrich the science fiction landscape by offering diverse narratives and perspectives.