Most modern roller coasters do not use a traditional "pulley" system in the way a crane or an elevator does; instead, they utilize a chain lift or a launch system. The most common method for getting a coaster to its highest point is a lift chain, which functions like a giant bicycle chain. A motor at the top or bottom of the hill pulls the chain, and "dogs" (metal hooks) under the coaster train latch onto the chain to be pulled up. However, some specialized coasters, known as cable lift coasters (like Millennium Force at Cedar Point or Expedition Everest at Disney), do use a system that more closely resembles a pulley. In these rides, a powerful winch pulls a steel cable attached to a catch-car, which hooks onto the train and pulls it up the hill much faster than a traditional chain. While it involves cables and drums, the mechanical advantage is provided by the winch rather than a complex block-and-tackle pulley system. Once the coaster reaches the top, gravity takes over, and no pulleys, chains, or motors are used to move the train through the rest of the circuit.