The far side looks like a different moon. It's rugged, cratered, and almost free of the dark plains that make up the 'man in the Moon'.

The crust on the far side is substantially thicker, so ancient lava had a much harder time reaching the surface after big impacts. On the near side it welled up and flooded the basins, making the dark maria. Why the crust is lopsided is still argued over. Earth's heat on the young Moon is one candidate.