Parachuting, or skydiving, is the action sport of exiting an aircraft and returning to Earth with the aid of gravity, then slowing down during the last part of the descent by using a parachute. It may or may not involve a certain amount of free-fall, a time during which the parachute has not been deployed and the body gradually accelerates to terminal velocity. Andre-Jacques Garnerin was the first to make successful descents using a canvas canopy and small basket, tethered beneath a hot-air balloon. The first intentional freefall jump with a ripcord-operated deployment is credited to Leslie Irvin in 1919. The military developed parachuting technology as a way to save aircrews from emergencies aboard balloons and aircraft in flight, and later as a way of delivering soldiers to the battlefield. Early competitions date back to the 1930s, and it became an international sport in 1952. Parachuting is performed as a recreational activity and a competitive sport, as well as for the deployment of military airborne forces and occasionally forest firefighters.