In FB, there are two very basic types of armor. There are Resistant and Absorbant armors. It's one of those stupid distinctions with bad names that you confuse the two, but oh well. See, you can have armor that is like Diablo or other things; i.e. it can break. Or you can get armor which takes hits for you until it disappears. Quake warriors have mixes of the two. Fallout style armor has resistances also, but it breaks.

Resistant: These armors can basically just another HP meter. They absorb damage until they crack. You take no or little damage until they are destroyed. Forcefields are mostly resistant. Rifts armors are also mostly resistant.

Absorbant: These armors are more like in Fallout or Final Fantasy. The armors don't break; it lessens each hit for you.