Lunar features are the physical characteristics present on the moon, such as the craters, maria and highlands. The maria are the dark, flat plains on the moon whereas the highlands are raised areas on the surface of the moon. These features are the result of the moon being hit by space rocks, asteroids and comets.
The maria are the dark-colored areas of the moon and are mainly seen on the near side of the moon, the side of the moon that always faces Earth; the far side of the moon contains very few of these plains. Maria are smooth and don't contain many craters. They are known to be younger than the highlands because areas with a greater number of craters are older. The maria formed when objects impacted the moon, cracking its surface and allowing lava to ooze through the cracks, spreading across the terrain. Rocks taken from the maria were found to be about 3.8 million years old. The lunar maria were once believed to be seas filled with water, but scientists have since found that this is not the case.
The lunar highlands are the lighter parts of the moon. Rocks found in these regions are about 4.2 billion years old. The highlands are filled with craters, including some that formed within other craters. The moon's craters are mainly the result of bombardment from space debris during the time when the solar system was still being formed.