Planes of Reality are what exist and don't exist in existence. They are a concept that is beyond the comprehension of many beings that exists in anything less than five dimensions of space.
“Airibron is a Plane of Reality located inside of the Plane Isilron. It is characterized as a...Airibron
“Isilron, the Plane of Creation, or Creation is a Plane of Reality that contains all of the other...Isilron
“Planes of Reailty, Planes, Possibilities, Dimensions, or Realms are infinitly numerous parallel...Planes of Reality