Science fiction and fantasy are two distinct genres of speculative fiction. Science fiction often explores futuristic concepts, advanced technology, space exploration, and the impact of science on society. It raises questions about what could happen in the future based on current scientific understanding, often featuring elements like robots, aliens, and time travel. In contrast, fantasy involves magical elements and mythical creatures, often set in imaginary worlds. It includes themes of heroism, adventure, and the battle between good and evil. Popular examples of fantasy include works featuring dragons, wizards, and enchanted realms, such as those found in J.R.R. Tolkien's novels.