Laplace's Demon is a thought experiment proposed by the French mathematician Pierre-Simon Laplace in the 19th century. It imagines a hypothetical intellect that knows the precise location and momentum of every particle in the universe at a given moment. With this information, the demon could predict the future and understand the past, as everything in the universe follows deterministic laws. The concept raises questions about determinism and free will. If the universe operates under strict laws of physics, as suggested by classical mechanics, then every event is predetermined. However, modern developments in quantum mechanics challenge this idea, introducing elements of randomness and uncertainty.