This sound is widely recognized from Garry's Mod, the Source-based sandbox game created by Garry Newman and released in 2004. Online, it spread through gameplay highlights, machinima, fail compilations and short meme edits where a player death needed an instantly readable punchline. Its staying power comes from how quickly it signals total failure without needing context. It fills a similar role to the roblox oof in game humor, but with a rougher, more chaotic feel tied to Source-engine antics and ragdoll comedy.