The Nine Realms are nine individual worlds that, while located in separate spiral galaxies[2], are systematically connected by the branches of Yggdrasil and orbit Midgard. The inhabitants of the realms are mostly associated with each other rather than the other advanced species residing beyond the realms. Earth, where humanity resides, is one of the Nine Realms, but its inhabitants are considered to be too underdeveloped by the other races to associate with.