Damage is stuff you absorb and it decreases you're health over time. Different things hurt you more then others. Like bullets from a Chinese Assault Rifle hurt more then a Lead Pipe to the leg. It also depends on what the weapon is, what kind it is, how good the user is, and how much resistance the receiver has. Also stealth kills do more damage, and it depends where you hit them, and what type of protection they have on.
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