Heaven, also known as the Afterlife, is the ultimate destination for the soul. Every race acknowledges a Creator spirit of some kind and the idea that there is a component of a creature that persists past the point of death.
Heaven exists near the edge of creation, a transitional space between all reality and the Source. It is guarded by the Heavenly Host, creatures called 'angels' that exist as pure willpower, fueled by wavelengths of energy known as the Power Cosmic.
The purpose of Heaven? That is unknown. It might be a well-deserved, permanent afterlife. Or a staging ground before reincarnation. Or a stepping stone to a higher plane of existence. The Creator alone knows, and even those who are ripped back to their mortal coil are not permitted to return with such knowledge. But it is, incontrovertibly, where the soul *goes* when it has reached Nirvana-- a state of enlightenment and completion.