A bulletproof vest is a piece of defensive equipment designed to attenuate the energy transmitted by high-velocity projectiles. Functionally, it operates by utilizing advanced composite materials, often involving layers of high-strength fibers such as aramids or ultra-high-molecular-weight polyethylene (UHMWPE). These materials are engineered to resist penetration by converting the kinetic energy of the incoming object into other forms of energy—primarily heat and strain—through controlled deformation and fiber failure. The structural integrity relies on the composite nature of the barriers, which distribute the force over a wider area, thereby achieving sufficient levels of ballistic resistance to shield underlying biological tissues while maintaining the objective criteria of minimal weight and maximum protection.