The phrase translates from Chinese as are you crazy, a blunt question often used when someone says or does something surprising, reckless or hard to believe. In short-form video and meme culture, brief spoken reactions like this travel well because they need no translation of the joke itself: the tone alone carries the disbelief. Creators reuse it as a quick verbal reaction, especially in comedy edits, gaming clips and chat-style videos, where a single incredulous line can replace a longer explanation and keep the pace fast.