The Law of Superposition is a fundamental principle in geology that states in any undisturbed sequence of sedimentary rocks, the oldest layers are at the bottom, and the younger layers are at the top. This means that as new sediments accumulate, they cover older ones, allowing scientists to determine the relative ages of rock layers. This law is crucial for understanding the geological history of an area. By studying the arrangement of layers, geologists can infer the sequence of events that led to the formation of various rock formations, including the presence of fossils and other geological features like faults and intrusions.