The Gummi Ship is the main method of transportation between worlds in the Kingdom Hearts series. Several characters, including King Mickey and Sora, as well as groups like the Heartless and the Nobodies, use Gummi Ships to move between Worlds. These ships are made entirely of Gummi Blocks, made of special Gummi material that allows to travel between Worlds. Gummi Ship travel is a slower, but a more reliable alternative to warping by using a Corridor of Darkness.
Although Gummi travel seems to have originated with King Mickey, it is now mostly handled by his loyal subjects Chip and Dale, as well as Radiant Gardenrefugee Cid and Pinocchio's father, Geppetto.