Demiplanes

Demiplanes are the most fluid of the planes, often bein created and destroyed the most regulalry, the planar energy simply being converted between them like thermal sciences or studies of other forms of energies. These smaller planes often had a finite size. They can be created by powerful casters, or were incomplete in the world's creation. These planes can be withing other planes or sit outside of these spaces. 

"I believe Demiplanes are created with the left over products of the world's creation. That there is a planar tie connecting everything, like wisps of spider webs, connecting every silky corner while some edges still blow freely in the wind, waiting for a spider to come along and continue its web" ~ Jameson Freewright

Demiplanes prove that some kindthe spaces of veil or connection is within or between planes.

Geography

Demiplanes can be everwhere and nowhere all at once, tied to the world with planar forces.

Ecosystem

Each demiplane will have its own living structure: in some no life could thrive, while others are abundant with life, oxygen, and resources.

Type

Plane of Existence