A creature with resistance to energy has
the ability (usually extraordinary) to ignore some
damage of a certain type each round, but it does not have total immunity.
Each resistance ability is defined by what energy type it resists and how many points of
damage are resisted. It doesn't matter whether the
damage has a mundane or magical source.
When resistance completely negates the
damage from an energy attack, the attack does not disrupt a spell. This resistance does not stack with the resistance that a spell
might provide.