What is a Plane?

The following text is taken from "The Manual of the Planes".

The Planes of Existence are different realities with interwoven connections. Except for rare linking points, each plane is effectively its own universe with its own natural laws. The planes are home to more powerful variants of familiar creatures and unique monsters, all of which have adapted to their strange environments.

The planes break down into a number of general types: Material Planes, Transitive Planes, Inner Planes, Outer Planes, and Demiplanes. These types aren't exclusive, but most planes fall neatly into one category.

--Posted 27 Jan 04 by OrchestralDarkness

Material Planes

These planes are the ones most familiar to characters and are usually the setting for a standard D&D campaign. The Material Planes tend to be the most earthlike and operate under the same set of natural laws. The D&D rules are designed with Material Planes in mind. Most campaign settings have only one Material Plane, acting as the "home base" for that campaign.

-Forgotten Realms

--Posted 27 Jan 04 by OrchestralDarkness

Transitive Planes

This mixed bag of planes are grouped together by a common use: getting from one place to another. The Astral Plane is used to reach other planes, while the Ethereal Plane and the Plane of Shadow are both used for transportation within the Material Plane they're connected to. These planes have the strongest regular interaction with the Material Plane and are often accessed by using various spells. They have native inhabitants as well.

-Astral Plane
-Ethereal Plane
-Plane of Shadow

--Posted 27 Jan 04 by OrchestralDarkness

Inner Planes

Also called planes of power, these realities are incarnations of the basic building blocks of the universe. They are made up of a single energy or element that overwhelms all others. The natives of Inner Planes are made up of these elements as well. The Inner Planes can be divided up into two groups: elemental planes, which symbolise the physical properties of the universe, and energy planes, which represent the creative and destructive forces of the universe. The planes of power are hostile to planar travelers, who should take care crossing them.

-Elemental Plane of Air
-Elemental Plane of Earth
-Elemental Plane of Fire
-Elemental Plane of Water
-Negative Energy Plane
-Positive Energy Plane

--Posted 27 Jan 04 by OrchestralDarkness

Outer Planes

The homes of beings of great power, these planes are also called the godly planes, spiritual planes, or divine planes. The deities themselves live here, as do creatures such as celestials, demons and devils. The Outer Planes tend to have alignments, representing a particular moral or ethical outlook, and their inhabitants tend to behave in agreement with those alignments. The Outer Planes are also the final resting place of spirits from the Material Plane, whether that final rest is calm introspection or eternal damnation.

-Abyss
-Acheron
-Arborea
-Arcadia
-Baator (The Nine Hells)
-Beastlands
-Bytopia
-Carceri
-Celestia (Seven Heavens)
-Elysium
-Gehenna
-Hades (Grey Wastes)
-Limbo
-Mechanus
-Outlands
-Pandemonium
-Ysgard

--Posted 27 Jan 04 by OrchestralDarkness

Demiplanes / Pocket Planes

This catch-all category covers all extradimensional spaces that function like planes but have measurable size and limited access. Other kinds of planes are theoretically infinite in size, but a demiplane might only be a few hundred feet across. Access to demiplanes may be limited to particular locations (such as a fixed gateway) or particular situations (such as a time of year or a weather condition). Some demiplanes are created by spells, some naturally evolve, and some appear according to the will of the dieties.

In Gatecrashers, the designator "Demiplane" indicates a larger plane, while "Pocket Plane" indicates a small plane. A plane that is composed of twenty areas would be considered a Demiplane, while one composed of three areas would be considered a pocket plane.

-The Fugue Plane
-The Hollow Hills
-The Pocket Plane of Grub

--Posted 27 Jan 04 by OrchestralDarkness