Hit point

Hit points or health points (HP) is the amount of damage a unit or building may take before being destroyed.

Terran

Healing

In StarCraft, medics may heal any biological unit, including zerg and protoss units, at an energy cost. A unit may be healed by one medic at a time.

In StarCraft II, medivac dropships replace medics in multiplayer and work the same way.

Repairing

SCVs may repair terran mechanical units and buildings at a resource cost. Multiple SCVs may repair the same object simultaneously, speeding up the process. Bio steel can repair battlecruisers slowly.

Structures

Terran structures lose 1 HP per second while their hit points remains below one-third of maximum. Structures may be destroyed if left to "burn down".

In StarCraft II single player, the structures can be upgraded to auto repair itselft to 50% health.

Zerg

Healing

All zerg units and structures slowly regenerate hit points automatically. Damaged units create damaged eggs when they morph, but regain full hit points when they complete morphing (from one unit to another). Structures do not regain any hit points when they complete morphing (from one structure to another).

The roach regenerates much more quickly while burrowed.

Without creep Zerg structures will die except for spine and spore crawlers. Both spore and spine crawlers can uproot itself to move to a different location to survive.

Queens

In StarCraft II, queens may restore a large number of hit points to a zerg unit or structure at an energy cost. The ability is called Transfusion.

Protoss

Shields

By themselves, the protoss have no way to regenerate hit points. Instead, part of their unit and structure vitality is invested in shields. Shield points must normally be depleted first before the underlying hit points are affected. Shield points regenerate automatically over time.

The protoss have both armor and shield upgrades.

In StarCraft, a shield battery may restore shield points at an energy cost. The science vessel's EMP Shockwave reduces all shields in the area of effect to 0 points. Some abilities, such as the defiler's Plague, ignore shields.

In StarCraft II, the ghost's EMP shot ability drains 100 shield points.