Fictional worlds are imaginative settings created in literature, film, or other media where stories unfold. These worlds can vary greatly, from fantastical realms like Middle-earth in The Lord of the Rings to futuristic societies in science fiction like Blade Runner. They often have their own rules, cultures, and histories that shape the narratives within them. These worlds allow creators to explore themes and ideas that may not be possible in the real world. They can include unique creatures, magical systems, and advanced technologies, providing a backdrop for characters like Harry Potter or Luke Skywalker to embark on their adventures.