Resistances

Damage Types and corresponding Resistances correspond to one of the following types:

Physical
Armor provides the most protection against physical damage. This includes most weapons, poison, etc.

Magical
Magic attacks tend to ignore armor. Magical resist encompasses magical damage not covered by specific elemental type.

Electrical
Most electrical attacks stun their target. This includes natural lightning, static charges, etc.

Cold
Cold tends to slow its target. Includes ice, snow, etc.

Heat
Attacks based on heat does damage over time. Includes actual fire, radiant energy (like the sun), etc.

Chaos
Chaotic magic is impossible to resist, and almost impossible to control.

External Reference

 * Magic, Combat, and Crafting Skills on the Shroud of the Avatar Forums