Sci-fi, or science fiction, is a speculative genre which builds on imagination. Sci-fi manga ask, "what if things were different?" They explore a new world, whether it's the world of the future or past, a present Earth with a changed history, a land that was previously unknown, or another planet entirely. The genre commonly features humanity's inquisitiveness and innovation, as they grapple with new technologies, new societies, or new frontiers in Outer Space.