It has long been noted by mankind that the Moon only ever shows us one side. Since the Moon rotates on its axis at the same time as it orbits the Earth, it would seem obvious that we should be able to see the entire Moon during the course of the lunar cycle.
This is not the case. As the Moon is rotating on its axis and orbiting the Earth, the Earth is also rotating on its axis. As we both rotate, it causes the situation where we can only ever see one face of the Moon. The ancients, staring up at this same face over long periods of time thought that there might be a face evident there, a man living in the Moon. Stories about the opposite side of the Moon (the “dark side” of the Moon) also arose into a popular mythology. Today men have actually visited the far side of the Moon, although we still cannot see it from Earth.
The single face of the Moon does provide for interesting viewing, however. Because we only ever see the one face, we know that what we are looking at is not going to change. The craters that we see tonight will be in the same place tomorrow night. It offers a wonderful continuity to our viewing.