Why does the moon revolve around the earth instead of falling like an apple?

In a sense, it is falling toward earth, but its orbital velocity causes it to miss from moment to moment. The moon is in a stable orbit around the earth, and that is due in part to the gravitational pull between the earth and moon, and in part to the moon's own velocity as it travels in its orbit. If we could put some unimaginably powerful rockets on the moon that would push sideways (not down toward earth) in such a way that the moon's orbital velocity would slow a great deal, then the moon WOULD fall to earth, and it would cause more trouble than a falling Apple.