Physical Damage
Physical is one of the types of damage in Diablo III.
Most types of weapons or open-handed attacks deal physical damage, as do most monster attacks.
Physical damage can not be resisted, but it may be reduced, blocked, or absorbed.
Critical hits scored with physical damage deal double damage, but do not pack any other bonus effect.
Damage Types
Blizzard's @Diablo Twitter feed added some clarification about damage types in posts made in early December 2010.[1]
any change in the range of damage types to include holy, shadow, voodoo or anything else to match the classes? —Scyberdragon
Damage types will likely change some but are currently Physical, Fire, Lightning, Cold, Poison, Disease, Arcane, and Holy. —Diablo
Fairly significant in their difference, but both countered with a single resistance. Damage/resists aren’t design complete though.—Diablo
Whats the difference between poison and disease damage?—WickedBubba
Disease has a damage debuff (both intake and output), and poison has a health debuff (regen/heal). Subject to change of course.—Diablo
Is there much difference between poison and disease? They’re both internal maladies that hurt over a period of time.—Grug