What is a hovercraft?

A hovercraft is meant not to fly high but to hover just above the surface of water and land. The propeller is on the bottom of the craft. When the propeller turns, it pushes air down, against the surface. A "skirt" around the edge of the hovercraft helps to confine the air, allowing the hovercraft to ride a short distance above the surface. A second source of thrust moves the craft forward. Instead of using the lift of a wing, the hovercraft rides on a cushion of air.