Health Bar

In Overwatch, your Health Bar on the bottom left corner of the hud has various colors representing various health types with their unique properties. The bar consists of Health Points (HP), Armor, Shield, and, if a lucio is on your team, Overheal. Naturally this is important because once that bar depletes, your hero dies and you must wait until you can spawn again.

Healthbar Diagram

STANDARD HEALTH 

White incremements represent Standard Health on the health bar.

The standard health is the last to be damaged, after the armor, shield, and overheal are depleted. 

Mercy's Health will be passively regenerated 25 health per second if she does not take damaged for 3 seconds.
Lúcio through his Crossfade: Heal can also regenerate his own Health.
soldier76 full portrait

Armor

Yellow (if innate) or Orange (if added via ability) increments represent Armor on the health bar.

Armor will block 5 damage form every individual hit that deals 10 damage or more.

Hits that deal less than 10 damage will be halved.

This means armor is especially effective against rapid fire/beam weapons (tracer, soldier, winston, etc.). 

Bastion, D.Va, Rienhard, and winston have innate armor.
 In addition, Torbjorn's armor pack can be used to grant 75-armor to any hero (however, this armor can not be "healed" back). 
<strong>Example:
</strong>If an attack does 10 damage per hit. And you hit the opponent 10 times. 
If it is Standard Health, it would take away 100 increments. 10 x 10 = 100. 
If it is armor, it would take away 50 increments. (10-5) x 10 = 50.
reinhardt full portrait

Shield

Light Blue increments represent shield on the health bar.

Shields will regenerate 25HP per second after 3 seconds of not being hit ("out of combat").

Symmetra, Zarya, and Zenyatta have innate shields. In addition, Symmetra Photon shield can be used to grant any hero a 25-shield
symmetra full portrait

Overheal

Dark blue increments represent overheal on the health bar.

Overheal grants heroes more health than their maximum, and decays rabidly. 

Currently, only Lucio's sound barrier (ultimate) can overheal. 
lucio full portrait

Environmental Healing

In addition to hero's abilities, the health bar may be restored through features on the map, including:

  • Small Health Packs (75-increment, has 10 second cooldown)
  • Large Health Packs (250- increment, has 15 second cooldown)
  • Payloads (10-increment per second)
  • Spawn rooms (100-increment per second)
Healthpack03