Armor

Armor is protective gear designed to absorb, deflect, or resist the impact of projectiles, blades, fragments, or other hazards. It can be worn by individuals or installed on vehicles, aircraft, and fixed installations, and may combine multiple layers and materials to improve performance.

Historically, armor evolved from leather and fabric coverings to metal defenses. In antiquity, bronze and iron plates, scale, and mail offered protection; by the late Middle Ages, full plate armor provided strong defense but reduced mobility. Armor declined with gunpowder firearms, though it persisted in ceremonial use and specialized roles.

Modern personal armor comprises soft armor and hard armor. Soft armor uses high-strength fibers (aramids such as Kevlar or Twaron) or ultrahigh-molecular-weight polyethylene to slow or stop projectiles through multiple layers. Hard armor uses ceramic plates or composite inserts to defeat higher-velocity rounds. Protective levels are described by standardized testing schemes (e.g., NIJ or VPAM).

Vehicle and structural armor employ steel, aluminum, ceramics, and advanced composites. Composite armor combines hard face ceramics with supportive backing to dissipate energy. Reactive armor uses tile-like modules that explode outward to disrupt penetrating charges. Active protection systems detect threats and attempt interception before impact.

Manufacture involves material selection, forming, heat treatment, and layering; performance depends on weight, coverage, and integration with mobility. Testing includes ballistic, fragment, and environmental tests. Standards such as NIJ levels IIA through IV and military STANAG 4569 ratings guide selection and procurement.

Armor remains central to military, law enforcement, and civilian protection. Limitations include weight, mobility, heat, and cost. Ongoing research explores lighter materials, modular systems, and smart armor capable of sensing damage and adapting to threats.