Body armor is a pickup in the Grand Theft Auto series that serves primarily to protect the player's health from specific forms of damage, most notably gunfire. In most cases, body armor in the games is illustrated as a protective blue vest.
First introduced in the original Grand Theft Auto, the body armor's primary function is to serve as padding for the player health, in effect extending the player's resilience to damage from gunfire, explosions and fire.
GTA 1 — GTA 2
In early top-down GTA games, armors in both GTA 1 (as well as Grand Theft Auto London mission packs) and GTA 2 serve their intended purpose, adding 10 more hit points to the player's existing health, but provides no protection to the player when they fall from great heights, are run over by vehicles, or are beaten up by the police and arrested. Armors are most commonly found spawned in specific locations or crates, and, in the case of GTA 2, can also be acquired by crushing specific cars.
GTA III — GTA Vice City Stories
Body armor continued to be featured between GTA III and GTA Vice City Stories, undergoing several more changes. In all its of its appearances, armor now offers nearly the same amount of hit points as the player's full health, doubling the player's resistance to damage. The armor hit points stayed the same until GTA San Andreas where the armor is now a bar instead of hit points. In addition, armor can now pad injuries from falls, collisions with vehicles on foot, and even melee attacks; the armor in GTA San Andreas and GTA Vice City Stories is an exception, providing no protection to the player from falls, while the armor in Grand Theft Auto Advance provides no protection to melee attacks.
In addition to spawning in specific locales, body armor can also be purchased at stores that sell weapons, such as Ammu-Nation, as well as entering the police/SWAT Enforcer trucks. Like the player's health, armor hit points between GTA Vice City and GTA Vice City Stories (sans GTA Advance) can typically be increased easily via side-missions (such as "Vigilante"), as well as 100% completion of the game.
The appearance of armor pickups has also changed significantly after GTA III. When included in GTA III, the pickup assumed the appearance of a shield icon; in games after, however, the pickup is redesigned as a spinning vest, possibly to avoid confusion with the police bribe pickup.
GTA IV — GTA Chinatown Wars
Armour in GTA IV has been refashioned slightly out of realism. It no longer offers protection to falls, collisions with vehicles on foot, or melee attacks (including hand-to-hand combat and melee weapons), increasing the player's chances of death from these hazards. Armour in GTA Chinatown Wars appears to revert to pre-GTA IV settings.
As expected, armor can be found lying about in specific points of the city (distinguishable by its red glow) as well as underground weapon dealers in GTA IV or AmmuNation.net in GTA Chinatown Wars. NOOSE Enforcers still provide the player some armor, but only gives the player roughly one third of the maximum amount (With the exception of GTA Chinatown Wars, which gives you full armor).
Grand Theft Auto V introduced a more complex Body Armour system, including five tiered body armour vests ranging from small arms protection to large caliber weapon and explosive protection.