Hard armor refers to protective gear made from rigid materials designed to absorb and deflect bullets and shrapnel. Commonly used by military personnel and law enforcement, hard armor plates are typically made from materials like ceramic, steel, or polyethylene. These plates are inserted into vests or carriers to enhance protection against high-velocity projectiles. The effectiveness of hard armor is often rated according to the NIJ (National Institute of Justice) standards, which classify armor based on its ability to stop specific types of ammunition. While hard armor provides superior protection, it can be heavier and less flexible than soft armor, which is made from materials like Kevlar.