Left 4 Dead is a cooperative first-person shooter developed by Valve and released in 2008, pitting up to four survivors against waves of infected in campaigns across abandoned cities, hospitals, and rural towns. Its tense sound design and fast, unpredictable infected became a defining part of late-2000s PC and console gaming, and the sequel followed in 2009. Streamers, editors, and fans still reuse its short audio cues because they instantly recall that frantic, four-player fight for survival, even for viewers who have never played the original game.