Life
Life is shown as a red orb in the lower left of the screen and will decrease as you receive damage. Characters die when they reach 0 life and must be resurrected in town. You can restore life by using flasks, gaining life regeneration from passive skills and equipment, or leeching life from enemies. Life is fully restored when you enter a town.
Every class starts out with 50 Life, and gains +12 per level giving a base life of 1238 at level 100. Strength increases Life, with every +10 node giving +5 Life. Characters do not begin with any life regeneration, but it is available from gear and passive skills.
Total maximum life can be calculated with the following formula:
Maximum Life = (38 + (Level * 12) + (Strength / 2) + flat life bonuses) * (100% + percent-based modifiers)
Flat life bonuses are added directly to your base life (+x to maximum life). Percent-based modifiers apply to flat life bonuses, as well as base life and life from strength (+x% increased maximum life). See Modifiers.
Passive skills
There are passive skills that grant life bonuses.
Life
These passive skills grant increased maximum life or additional base maximum life.
Totem life
These passive skills grant increased maximum life for totems.
Minion life
These passive skills grant increased maximum life for minions.
Miscellany
These passive skills are related to life, but do not fit into any other category.