Health, or HP represents the state of your character and how much damage they can take before death. All players have 40, except VIPs which have 400HP. It is possible to increase health up to 40HP through using the health pack, up to 10 HP at a time, as well as Bandages. Health Packs and Bandage do not work on VIPs.
While we do not directly see it, damage is applied as decimals. This is important as our displayed health is not. An example of decimals is the AN 94, which applies 2.5 damage. When used, you would see pairs of 2 and 3 damage being done. Rather than applying a random damage of 2 or 3, the game subtracts 2.5 damage from a player's health and then rounds the player's health up on the display (but not the actual health). So if a player had 40 HP and was hit with 2.5 damage they would have 37.5 health left, but it would be displayed as 38. The 2nd hit would cause the health to drop to 35, and the next to 32.5 which would be displayed as 33. If 10 shots were taken at 2.5 damage, a total of 25 damage would be applied each time.
This is also true of perks, such as the Shelter perk. This perk decreases damage taken and damage done to 10% of it's damage. So while many damages would be 0.xx, these do add up and will cause damage.
- In the early beta, it used to be possible to be alive with 0 displayed health. This would happen due to a player having a 0.x health left.