Composed with assistance from this Source:
The Barrier does NOT block the following:
- Melee attacks. Reinhardt and his shield will both take full damage from a single melee attack.
- Sombra's EMP will destroy his shield, and hack everything that was behind it.
- Orisa's halt ability will pass through it, however it will not suck his allies from behind a barrier if it detonates on the other side.
- Some channeled weapons, including: Winston's Tesla Cannon, but Symmetra's Photon Projector beam will be blocked.
- Reinhardt's Fire Strike and Symmetra's Photon Orbs.
- Hanzo's Dragonstrike
- Junkrat's Rip Tire
Fire Strike and Photon Orbs can actually pass through and damage
everything in its path, including Reinhardt, his barrier and anyone
else behind Reinhardt.
Do also note that Reinhardt's shield does not block ally projectiles. This means you should combo with a Bastion or any other front line assault that will make best use of your shield.
- Health or HP is your total life + shield + armour.
- Life is simply a number that represents how much damage you can take before you die.
- Armour reduces incoming damage.
- Shield self-regenerates over time.
Basically, armour and shield are similar to life, in that they contribute to your overall health, but they come with special attributes. A hero can have a mix of life, armour and shield that makes up their total health pool.
Shield will deplete before armour or life does, and armour will be damaged before life is.
Armour
Reduces incoming damage by 5 if the hit was 10 damage or more. If the damage is less than 10 then it is halved.
If a hero has innate armour, such as D.Va, then they will regain it through normal sources of healing (health packs, Mercy, etc). However, other sources of armour such as Torbjörn's armour pack are temporary bonuses and will be depleted from the hero once they run out and you will have to pick up another one.
For example:
- Winston has 400 life and 100 armour for a total of 500 HP.
- Soldier: 76 shoots a bullet that should deal 15 damage.
- The bullet hits Winston but because he has armour it only deals 10 damage.
- Winston has 400 life and 90 armour remaining.
Tracer shoots very quickly but each bullet doesn't hit hard. If her bullet does 4 damage, then armour will reduce it to 2 damage (halved).
Armour is more effective against smaller firearms such as Tracer and less effective against heavy-hitters such as Pharah and Junkrat.
Heroes such as D.Va have lots of innate armour (400 life and 200 armour).
Shield
Does not reduce incoming damage.
After three seconds of not taking damage, shield will regenerate at a rate of 25/sec.
Heroes such as Zenyatta have innate shield (50 life + 150 shield). Normal sources of healing will restore both the hero's life and shield.
Other abilities such as Zarya's Projected Barrier, Reinhardt's Shield or Winston's Barrier Projector are not shields in this sense. Instead, they are referred to as barriers and usually have their own health pool that is separate from the hero.
Best Answer
So for this, we tested using Zarya's self-damage on her secondary fire since we only had two people. Let's establish the expected behavior:
No armor.
That's 23 damage dealt to Zarya without armor.
Now, let's get to the meat of the question.
With armor, damage on shields.
This is also 23 damage dealt to Zarya's shields while she has armor from Torbjorn's armor pack. But let's give it one more trial.
With armor, damage on armor.
269 - 254 = 15 damage dealt to her armor. While this is a bit more than the expected 5 damage reduction, it's still reduced damage which means that self-damage is mitigated by armor.
Conclusion
This means that we can definitively state that, at least for now (6/30/2016), the damage reduction provided by armor does not apply to shields.