The term 'Tireless Transportation' can be summarized as SLED, a four letter word. Sleds are vehicles that are pulled by animals or people and have been used for centuries as a form of transportation. They are often used in cold climates, such as the Arctic, where they are an efficient way to move goods and people over snow and ice. Sleds are also popular for recreational activities, such as sledding and dog sledding. They are lightweight, easy to maneuver, and require no fuel, making them a tireless form of transportation.