Simulation Theory suggests that our reality might be an artificial simulation, similar to a computer program. This idea posits that advanced civilizations could create highly sophisticated simulations that are indistinguishable from actual reality. If this is true, it raises questions about the nature of existence and consciousness. Philosopher Nick Bostrom popularized this concept in 2003, arguing that if many simulations exist, it is more likely that we are in one rather than the original reality. This theory intersects with discussions in philosophy, technology, and artificial intelligence, prompting debates about the implications of living in a simulated world.