The moon is earth's satellite. The only (natural) satellite earth has. 
The moon orbits around earth once a month. As this happens, the angle between the Earth, the Moon and the Sun changes; we see this as the cycle of the Moon's phases. The time between successive new moons is 29.5 days (709 hours), slightly different from the Moon's orbital period since the Earth moves a significant distance in its orbit around the Sun in those 29.5 days.

The first spacecraft that visited the moons was Luna 2 in 1959.
The first time people landed on the moon was on july 20th 1969, the last one in december 1972. The moon is the only extraterrestrial body to be visited by human beings.  It is also the only from which samples have returned to earth.

The gravitational forces between the earth and the moon cause several effects. The effect we notice most is the tides. The gravitational field of the moon "pulls" the sea from earth towards the moons. This creates two small bulges. One on the side of the moon, reaching towards it, and one on the other side of earth. Because of this effect, the tides change twice a day.

The moon has no atmosphere. The moon does contain water in the deep craters which have eternal shades. Water has also been spotted on the north pole.
The moons crust is 68 km thick (average). Below the crust is a mantle, and probably a small core. The moon's mantle is only partially molten, unlike earth's mantle.

Most rocks on the surface of the Moon seem to be between 4.6 and 3 billion years old. This is a fortuitous match with the oldest terrestrial rocks which are rarely more than 3 billion years old. Thus the Moon provides evidence about the early history of the Solar System not available on the Earth.

Pictures of the moon and it's surface will be added soon!!!