Damage Reduction for Barbarians

[wayavas]

At 7th level, a barbarian gains damage reduction. Subtract 1 from the damage the barbarian takes each time she is dealt damage from a weapon or a natural attack. At 10th level, and every three barbarian levels thereafter (13th, 16th, and 19th level), this damage reduction rises by 1 point. Damage reduction can reduce damage to 0 but not below 0.

So as I understand, this damage reduction is only for weapons or natural attacks. But, isnt DR/- means that it is reducted from every source?
Because if this damage reduction is only for weapons and natural attacks, then it should say something like DR/Magic or something like that?

[concerro]

DR is only for weapons. Natural attacks are also weapons.

DR/- just means no weapon can bypass it.

When you see something like DR/magic it means it takes a magical weapon to bypass it.

[Name Violation]

elemental damage is never applied to DR. thats what energy resistance is for.

dr applies to physical sources of damage (arrows,claws, hammers, ect), but not fire, or cold, or force, or sonic, ect

dr/bludgeoning means you need a bludgeoning weapon to overcome the dr
dr/- means nothing overcomes it physically, but acid or electricity does normal damage.

[Arbane the Terrible]

Note that DR only works against non 'energy' attacks - stuff like fire or acid uses Resistance instead.