In many spiritual traditions, complex metaphysical philosophies and even quantum physics, there is the notion that there are 3 planes or spheres that categorize existence, all of which house different levels of information and require different forms of "technology" to understand.

In Vedanta, Buddhism, Hinduism, Sufism, Gnostic Christianity and Kabbalah these spheres are often referred to as the gross/physical, subtle/astral and mental spheres. Each sphere, or plane, has a function and interacts and overlaps with one another and helps to create the totality of existence. The mental world transverses and influences the subtle world which transverses and influences the physical world, kind of like a nesting doll. Each plane houses its own set of rules and guidelines, much like the laws of gravity we recognize in the physical world.

In most of the aforementioned traditions there is the belief that the only Reality or Truth that one can achieve comes when the consciousness has transcended all three spheres and perceives the Divine which is independent of these spheres yet manifests them simultaneously.