Health and Armor have same purpose which is DEFENSE, but they are completely different things.
Health : The ability you can stand with the upcoming damage.
Armor : The thing that helps to protect you from overal upcoming damage.
For example : When it's cold and we go outside without thick clothes, we are likely to die in 1-2 hours (That's our health that can stand with cold weather for 1-2hours), but if it's cold, and we go outside with thick clothes, we are likely to die in 5-6 hours. (Thick Clothes are considered as Armor which helps us to recieve lesser damage than normal one).
HOPE I ANSWERED UR QUESTION! XD

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