The Jockey is one of the Special Infected introduced in Left 4 Dead 2, Valve's cooperative zombie shooter released in 2009. In the game it leaps onto a survivor's back and steers them away from the group while laughing maniacally, making its giggle an instant warning sign for players. Clips of that laugh spread through gameplay videos, compilations and soundboards, where it became shorthand for a sudden ambush or mischievous attack. It remains popular because the sound is instantly recognisable to fans and works just as well as a joke as it does as a scare.