Strafe jumping

Strafe-jumping is a technique used to increase a player's speed in computer games based on the Quake engine. The technique is common in Quake II, Quake III Arena, Quake 4, QuakeLive, Quake Champions, OpenArena, CodeRED: Alien Arena, Nexuiz, Xonotic, Cube, Jedi Knight II, Star Wars Jedi Knight: Jedi Academy, Soldier of Fortune II, Doom 3, Warsow, Digital Paintball 2, Call Of Duty, Return to Castle Wolfenstein, Wolfenstein: Enemy Territory, Tremulous, Unvanquished, Reflex, Counter-Strike, Titanfall and Titanfall 2.

Strafe-jumping started as a bug in the Quake code base, but it was later decided to be kept intact, as it had become a standard technique used by players. The bug itself relies on mathematics: when pressing a direction key, the game adds a unit vector in that direction to the player's movement speed. The final sum, however, is never normalized - this means that by directing the avatar away from the current kinetic vector but within 90 degrees of it, the player can exceed its own top speed.

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