An alien invasion refers to a hypothetical scenario where extraterrestrial beings, often called aliens, arrive on Earth with the intent to conquer or colonize. This concept is popular in science fiction, where stories often depict advanced technologies and conflicts between humans and these otherworldly visitors. In popular culture, alien invasions are portrayed in movies, books, and video games, showcasing various themes such as survival, resistance, and the potential for cooperation. Notable examples include films like Independence Day and War of the Worlds, which explore the challenges and consequences of such encounters.