Resistance To Damage

These are, it should be noted, enhancement qualities.  One can get perfectly mundane, 0 point armor, which will stop non-enhanced weapons, and even slow down 1 and 2 point enhanced damage weapons.  Weapon and armor qualities are roughly equivalent, a four point weapon will nullify most to all of the benefit of four point the same time, the armor is effectively knocking down the amount of damage the four point weapon inflicts to that of a more normal weapon of that type.  A weapon one step weaker than the armor it faces will require a serious warfare advantage, a weapon two steps weaker will take a severe one to get through, and if it's three steps weaker, you'll probably never hurt them.  [For example, trying to use a mundane, 0 point weapon to get through 4 point armor, you can probably forget about it.  Or a 1 point weapon vs 8 point armor.]  Weapons higher ranked than armor will simply slice through armor as if it wasn't there.

Offensive magic (fireballs, lightning, etc) will be reduced or stopped entirely by armor, dependent on the psyche of the user and the nature of the attack vs. the nature of the armor (Metal armor won't stop lightning very well, for example)