A fictional universe is a self-consistent fictional setting which contains its own backgroun elements including history and geography, and possibly also fantasy or science fiction elements such as magic or a means of faster than light travel, or other derived background elements. A fictional universe may also be called a fictional realm, imaginary realm, fictional world, imaginary world or imaginary universe. Most fictional universes are based directly or indirectly on our own universe, like the familiar "with a twist" world depicted in the popular Harry Potter series.