The Hawaiian Islands are a group of volcanos that have risen up over a "hot spot" of molten rock that wells up from deep in the earth's interior. As the ocean floor slowly moves over this spot, islands are born. They are then carried towards the northwest. The chain of Hawaiian islands were formed in the order: Kauai, Oahu, Maui, Hawaii.
Because of this age difference, each of the Hawaiian islands exhibits a distinct character. The younger island, Hawaii, has the highest summit and active volcanic features, but relatively smooth topology, like all the islands had when they rose out of the sea. Much of it is relatively arid and covered in bare lava fields. The oldest island, Kauai, has dramatic scenery formed by erosion, and the lushest vegetation. The other Hawaiian islands are in between, with Oahu having more fluted eroded mountains than Maui, where the dormant crater is younger and higher, and could still spring back to life.