Kinetic barriers, commonly called shields, provide protection against most mass accelerator weapons. Whether on starships or a soldier's suit of armor, the basic principle remains the same.
Kinetic barriers are repulsive mass effect fields projected from tiny emitters. These shields safely deflect small objects traveling at rapid velocities. This affords protection from bullets and other dangerous projectiles, but still allows the user to sit down without knocking away their chair.
The shielding afforded by kinetic barriers does not protect against extremes of temperature, toxins, or radiation.