The phrase who are you has become a staple reaction line online because it captures instant confusion in three simple words. Short clips built around the question circulate on soundboards and in meme edits, where the audio is detached from any original scene and reused for new situations. It is commonly paired with freeze frames, zoom ins, and identity reveal jokes, and its popularity comes from how flexible it is. The same line works for a genuine question, a suspicious confrontation, or a purely comic misunderstanding between characters.