A hovercraft is a type of air-cushion vehicle designed to travel over a surface by creating a cushion of pressurized air beneath its hull. The operational principle relies on the application of fluid dynamics, wherein powerful fans or engines are used to force a large volume of air into a skirt or plenum chamber underneath the craft. This pressurized air reduces the effective weight of the vehicle and lifts it a short distance above the ground surface. Propulsion is achieved either through directional airflow or by using separate engine systems to move the elevated body. Because the vehicle does not maintain continuous physical contact with the underlying surface, it is able to traverse varied terrain, including water, mud, and uneven ground, where conventional wheeled or tracked vehicles might struggle.