Wingsuit flying is essentially skydiving while wearing a suit with fabric stretched between the legs and under the arms. When the arms and legs are spread, the suit acts as an airfoil, allowing the skydiver to remain airborne for much longer than a normal free fall.
Wingsuit fliers usually launch themselves from airplanes or gliders, but launching from mountain tops or high cliffs is also common. With practice, a flier can soar for great distances and perform a variety of acrobatic maneuvers before deploying the parachute. Wingsuit flying requires a high level of expertise. Accidents are not uncommon and are nearly always fatal. Only accomplished, experienced skydivers are licensed for wingsuit flying.