Auto-aim

Aim assist, or assisted aiming, is a gameplay feature used in the Halo first-person shooter titles that assists the player in targeting an opponent. It is often mistaken as "auto aim", a common gameplay feature that locks the target for the player, shifting their focus from aiming to movement and strategy.

Overview
There are four types of aim assist in Halo titles: Snapping, Friction, Acceleration, and Magnetism.
 * Magnetism defines and outlines how far a bullet will "bend" in order to hit an enemy. Bullets and projectiles do not necessarily travel in a straight path; they will curve very slightly in order to hit a target. Different projectiles will experience different curvatures.
 * Snapping reorients the gun barrels toward enemies whenever a player's reticle are in proximity to their target.
 * Acceleration makes it so that when the player pegs their aiming stick in one direction the player's reticle will start moving slowly in that direction then pick up speed.
 * Friction slows the player's turn rate as soon as their reticule passes over an enemy. What it does is that it slows the player's top speed, and then dramatically decrease the rate at which the crosshair will slow down when the player release the stick.

Statistics
Note that range calculations are rough, and are based on the fact that Spartans and Elites are seven feet tall.

Aimbot
The game can be modded to repurpose the game's aim assist feature to create "aimbots". A typical aimbot, once activated, will automatically lock on to the nearest target whenever the designated button is pressed. Usage of an aimbot ("aimbotting") is considered cheating and usually results in a server ban and a suspension or deletion of an Xbox Live account.

External link

 * Wikipedia on aimbot