Why is one side of the moon called the dark side of the moon and?

The term "dark side of the moon" is a misnomer; it actually refers to the "far side" of the moon that is permanently hidden from Earth's view due to synchronous rotation. Both sides receive sunlight, but the far side is not visible from Earth. This side was first observed by humans during the Soviet Luna 3 mission in 1959, revealing its rugged terrain and cratered surface, which contrasts with the familiar features of the near side.