The effect of gravity has given the Moon a rotational period that is the same as its orbital period around the Earth. So as it goes around the Earth every 28 days, it slowly spins at the same rate (even though the Earth spins at a much faster rate beneath it).
Tidal Locking
The moon is 'tidally locked' with earth. Planets and moons are not made of purely smooth, evenly-distributed material. They have lots of bumps and bulges, even if their overall shape is spherical. The side of the moon that faces earth represents the more massive side of the moon. Over a very long time, the mutual tidal and gravitational forces between the Earth and Moon caused the more massive part of the Moon to always face Earth. All orbiting bodies have a tendency toward this tidal locking, but again, it takes an enormous amount of time and also depends on the rate of rotation of the body.
Seeing Along the Edges
Interestingly, there is a phenomenon called 'libration', which causes the Moon to apparently wobble from side to side and also a little up and down. [Think Libra, the scale. Imagine a balance scale slowly moving up and down until it settles.] The Moon is not actually wobbling. It is the result of a practically constant rotational rate for the Moon on its axis, and the fact that the orbital velocity of the Moon around the Earth is not constant. Because the Moon's orbit is elliptical, it revolves more rapidly when it is closer to the Earth. Also, some of the libration happens because the Moon does not orbit around the Earth exactly in the Earth's equatorial plane. This means we can 'peek' a little above and a little below the usual horizon of the Moon. Over a period of about 15 years of lunar observation from Earth, we see about 60% of the Moon's surface as a result of all that libration.
The new moon phase occurs when the moon lies between the sun and Earth, with the side facing Earth in shadow. This position causes the moon to be not visible from Earth as the illuminated side faces away.
A waning crescent is a phase of the moon where only a small sliver of the moon's illuminated side is visible from Earth. This occurs as the moon travels in its orbit around the Earth and the angle between the sun, Earth, and Moon changes, causing less of the illuminated side to be visible.
because that side is the side earth is facing
The "near" side of the moon is the side that always faces Earth. The "far" side of the moon can only be seen from space. The dark side of the moon is the title of a Pink Floyd album. There is no side of the moon that is always dark.
The dark side of the moon refers to the side of the moon that is not visible from Earth due to synchronous rotation, not because it is always dark. Both sides of the moon receive sunlight, but we only see one side from Earth.
The New Moon is when the lit side of the moon is facing away from Earth, and only the dark side is visible.
The new moon phase occurs when the moon lies between the sun and Earth, with the side facing Earth in shadow. This position causes the moon to be not visible from Earth as the illuminated side faces away.
cause we are asleep
Yes, but not on the dark side of the moon
A waning crescent is a phase of the moon where only a small sliver of the moon's illuminated side is visible from Earth. This occurs as the moon travels in its orbit around the Earth and the angle between the sun, Earth, and Moon changes, causing less of the illuminated side to be visible.
because that side is the side earth is facing
The "near" side of the moon is the side that always faces Earth. The "far" side of the moon can only be seen from space. The dark side of the moon is the title of a Pink Floyd album. There is no side of the moon that is always dark.
One side of the moon (the Earth facing side) becomes fully visible at Full Moon.
When the side of the moon facing Earth is dark and not visible, it is called the "new moon" phase. During this phase, the sunlit side of the moon is facing away from Earth, making it appear dark from our perspective.
The dark side of the moon refers to the side of the moon that is not visible from Earth due to synchronous rotation, not because it is always dark. Both sides of the moon receive sunlight, but we only see one side from Earth.
That isn't the answer. The reason why only one side of the moon is visible from the surface of the Earth is that the moon always keeps one side facing the Earth, which requires it to rotate once for each revolution of its orbit.
Only during a lunar eclipse, which can only happen during a full moon. The visible phases of the moon are caused by it changing its position relative to Earth and the sun. The visible portion is the moon's day side; the side facing toward the sun. The unlit portion is the night side, facing away from the sun.