This clip comes from Half-Life, Valve's landmark first-person shooter released in 1998, and features the frightened voice of a scientist NPC. Sounds from Half-Life have stayed popular in online edits because the game's audio is so distinctive and instantly readable. The scientist scream shows up in retro gaming memes, source-engine compilations and short reaction edits whenever creators want a quick burst of panic without a long vocal line. Its brevity helps it fit cleanly into fast cuts and punchy joke timing.