Transportation is any method of moving around the world that is faster than running. Currently, there are two vehicles in Minecraft: the Boat and the Minecart. As of Update 1.6, there are now Horses. Riding a saddled pig also counts as transportation. There are also Portals in the game.
Boats are small, wooden crafts that are used to cross bodies of water. They are crafted with 5 Wooden Planks. They break into 3 Oak Wooden Planks and 2 Sticks if crashed on shore at too high of a speed.
Minecarts are rideable carts that run on Rails. They are crafted with 5 Iron Ingots. There are multiple variants of minecarts, including Minecart with a chest, a Minecart with TNT, a Minecar with a Hopper, a Minecart with a furnace, and a Minecart with a Command Block.
Horses are a tamable Mob that, when tamed, can be equipped with a saddle and ridden. They are by far the fastest mode of transportation in Minecraft. Horses also have the capability to jump very high. Horses can be found mainly in Plains biomes. Horses also have a chance to spawn as a Donkey. Donkeys can be equipped the same way horses can. However, they can also hold a chest with items in it.
Distance traveled in the Nether is in a ratio of 8:1 to the overworld. This means that walking through the Nether is faster than any mode of transport in the overworld. If minecarts, horses, or pigs are used in the Nether, then travel times will be reduced even more.