The theory of continental drift was one of the earliest ideas explaining how the continents move. The theory of continental drift suggests that the continents drift across the ocean and are not stationary on earth's surface. Alfred Wegner proposed that all of the continents on Earth were once fitted together into a single super continent that he named, "Urkontinent". Wegner thought this was why the west coast of Africa and the east coast of South America seem to fit so well together and why similar fossils had been found in both locations.
Wegner never explained exactly how the continents drifted though and the theory of continental drift has been replaced by the theory of plate tectonics.