Tibetan mandala Kalachakra cosmogony (buddismnews.blogspot.com)
The Buddhist universe consists of thirty-one planes of existence (see chart). Every being lives on one or another of these planes. After death all beings, except arahants, will be reborn in a realm and under circumstances that accords with their karma — their volitional actions of body, speech, and mind willed and accumulated in that or any previous existence.
The lowest area (Planes 1-11) is called the Sensuous Sphere; sense experience predominates. Next comes the Fine-material Sphere (12-27) attained by practicing the fine-material absorptions (rupa-jhanas). Above that is the Immaterial Sphere (28-31) attained by practicing the immaterial absorptions (arupa-jhanas).