Wallhack

Cheating in online games is defined as the action of pretending to obey the rules of the game, while secretly subverting them to gain an unfair advantage over an opponent. Depending on the game, different activities constitute cheating and it is either a matter of game policy or consensus opinion as to whether a particular activity is considered to be cheating.

Cheating reportedly exists in most multiplayer online games, but it is difficult to measure. The Internet and darknets can provide players with the methodology necessary to cheat in online games, sometimes in return for a price.

An aimbot (sometimes called "auto-aim") is a type of computer game bot used in multiplayer first-person shooter games to provide varying levels of automated target acquisition to the player. While most common in first person shooter games, they exist in other game types and are sometimes used along with a TriggerBot, which shoots automatically when an opponent appears within the field-of-view or aiming reticule of the player.

Aimbotting relies on the fact that each player's client computer receives information about all the other players, whether they are visible from the player's position on the playing field or not. Targeting is simply a matter of determining the location of any opponent relative to the player's location and pointing the player's weapon at the target. This targeting works regardless of whether the opponent is behind walls or too far away to be seen directly.

Some servers allow inactive players to spectate, watching the game from the viewpoints of the active players. Recording of gameplay actions is also often possible. If someone was using a targeting aimbot, the bot would be plainly obvious to the spectator as unnatural exact position tracking. Some aimbots and triggerbots attempt to hide from spectators the fact they are being used through a number of methods, such as delaying firing to hide the fact it shoots the instant an opponent is in the cheater's crosshair. Some Triggerbot programs can be easily toggled on and off using the mouse or keyboard.

It is worth noting, however, that some cheat programs are a suite of many different features, incorporating many or all of the above as well as including options for ESP and other cheats such as affecting player movespeed, ammocount, always-on radar or enemies on map, etc., and such a suite can be colloquially called an "aimbot program".

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Wikipedia