A method for dealing with projectiles where the impact point is calculated and nothing else. There's absolutely no way for anything to get in between or dodging after the weapon has been discharged as there's no projectile to dodge or intercept.
Name variations: hit-scanning, hit scanning, hitscanning
The first video game about Hitscan was released on December 10, 1993.
Note that hitscanning does not remove the potential for rendering graphic trails, smoke, etc. that would indicate there was an actual projectile. This is one of the reasons hitscanning is used, it allows the projectiles to be resolved instantly, while the extra "fluff" can exist regardless of it, saving network resources for synchronizing actual projectile flight. For non-multiplayer instances it saves processing power for instances that don't produce delayed effects.