Armor:
Armor subtracts from damage recieved, though it must be on the area hit to defend against damage. Note that area/hit-many/hit-all attacks are blocked by the main armor value (body armor). Armor must be bought, and the statistics of the armor will be known to the mun (and the character, if he knows enough about such things) before the item is purchased. Some armors are better-crafted than others, and may have hidden bonuses, while some may have hidden flaws; these will not be revealed until the armor is safely in the user's inventory.

DR stands for Damage Resistance, and is the amount of damage that is subtracted before your character actually takes damage. Note that multipliers for weaknesses, resistances, and so forth are applied after armor DR, but before body DR.

Normal clothing: 0 DR (before enchantments.)
Light leather/heavy clothes/hat: 1 DR.
Heavy leather jacket/etc.: 2 DR.
Leather armor/cap: 2 DR.
Studded leather armor: 3 DR.
Chain mail/chain coif/Kevlar vest/crash helmet: 4 DR.
Scale mail/light body armor: 5 DR.
Plate mail/plate helm/medium body armor: 6 DR.
Heavy plate mail/great helm/riot helmet: 8 DR.
Heavy combat armor: 10 DR.

Material modifiers:
Bronze: -1 DR to metal armor.
Mithril: +1 DR to metal armor.
Adamant: +2 DR to metal armor.

Shields:
Yes, shields have an HP value. They are damn good at blocking, but when they break, you're SOL, as the saying goes.

Shields:
Buckler: Armor 1/+d5 to block. HP 5.
Small Shield: Armor 2/+d10 to block. HP 8.
Medium Shield: Armor 3/+d15 to block. HP 12.
Large Shield: Armor 4/+d20 to block. HP 15.

Material modifiers:
Bronze: *2 HP
Steel: *4 HP
Mithril: *8 HP
Adamant: *20 HP

Shields block some damage automatically. Blocking sends all blocked damage to the shield. Note that there are spells that can block damage as well; these are listed within the Spells section.

The Shatterproof enchantment improves DR; armor that cannot be broken is very good at keeping the person within unbroken as well.

Shatterproof 1: +1 armor. Normal wear and tear on the armor is ignored; shield HP is doubled.
Shatterproof 2: +2 armor. Severe wear and tear on the armor is ignored; shield HP is *5.
Shatterproof 3: +4 armor. The armor doesn't take damage, in any form. Shields don't take damage without extreme circumstances being involved.

Force Screens:
Force screens are all-around protection devices used to defend the wearer/vehicle in question from assault. Screens have a DR and HP rating; damage up to half the screen's DR is completely ignored, further damage inflicts a minimum of 1 HP damage to the screen itself. In addition, the user within takes 1/5 of the damage the shield blocks from being battered about - for instance, if a missle hit a shielded character for 60 points damage (and the shield held), the character within would take 15 points of damage, minus any body armor being worn, from the sheer impact. A screen's present DR is proportionate to HP remaining - a screen that begins at DR 10, 40/40 HP would be at DR 5 when at 20/40 HP. Therefore, even if the initial gunfire of an enemy may seem to affect the shields little or not at all, the snowball effect will eventually cause the shields' collapse (and the probable destruction of the character within, if the enemy is still firing by then.)