This sound is widely recognized as Nelson Muntz’s trademark “Ha-ha” from The Simpsons, the long-running animated television series. Over the years it spread far beyond the show through meme edits, reaction videos and short social posts, where it became a quick shorthand for playful ridicule. It is still popular because the delivery is instantly understood and works in many contexts, often alongside a buzzer or a bruh reaction when someone gets something badly wrong.