Left 4 Dead is a cooperative zombie survival game developed by Valve and first released in 2008, built around fast, tense runs through infected areas with a small team of survivors. Its in-game audio has long been shared by players on soundboards and in gameplay videos, where short clips are reused as reactions, transitions, and jokes outside the original game. Because the sounds are instantly tied to that frantic co-op experience, they remain popular with streamers and editors who want a quick, recognisable gaming reference without explaining the joke.