Bazinga became Sheldon Cooper's signature catchphrase on The Big Bang Theory, the long-running American sitcom that began in 2007. Sheldon uses the word to flag that he has just told a joke, often after a deadpan setup that leaves other characters unsure whether he is serious. Fans repeated it in forums, reaction videos, and merchandise, and it soon entered everyday slang as a playful way to say gotcha. Its short length and instantly recognisable nerdy delivery have kept it useful for memes, pranks, and reaction edits long after the show's original run.