True-or-false prompts have long been a staple of quizzes, game shows, classroom games and social media challenges, because they invite an instant reaction with no special knowledge required. The phrase 'true or untrue?' works in the same way online, giving short-form creators a quick way to frame a claim, a myth or a surprising fact before testing their audience. It fits reaction videos, trivia edits, polls and story posts, where the question itself becomes the hook. Its appeal is in its simplicity: one question, two possible answers, and a clear reason to keep watching for the result.