The experience of beings in samsara is traditionally schematized into six general categories, referred to as realms or worlds. They are the result of previous action or karma. None of these states is satisfactory, through the degree ofsuffering in them varies. The three upper or fortunate realms, where suffering is alleviated by temporary pleasures or where pleasure predominates, are the heavens of the mundane gods, the realms of the asuras or demigods, and the world of human beings. The three lower realms, in which suffering predominates over all other experiences, are those of the animals, the hungry ghosts, and the hells. [LLB 2002]