A MOON LANDING IS THE ARRIVAL OF A SPACECRAFT ON THE SURFACE OF THE MOON. THIS INCLUDES BOTH MANNED AND UNMANNED (ROBOTIC) MISSIONS.
In order to go to the Moon, a spacecraft must first leave the gravity well of the Earth. The only practical way of accomplishing this currently is with a rocket. Unlike other airborne vehicles such as balloons or jets, a rocket is the only known form of propulsion which can continue to increase its speed at high altitudes in the vacuum outside the Earth's atmosphere.
In order to land intact it must decelerate to less than about 160 kilometres per hour (99 mph) and be ruggedized to withstand a "hard landing" impact, or it must decelerate to negligible speed at contact for a "soft landing" (which is the only viable option with human occupants).
The United States' Apollo 11 was the first manned mission to land on the Moon, on 20 July 1969.
To date, the United States is the only country to have successfully conducted manned missions to the Moon, with the last departing the lunar surface in December, 1972. A total of twelve men have landed on the Moon.