Au Clair de la Lune is a traditional French folk song known for its simple, instantly recognisable melody and its opening line about moonlight. The M Adoul clip borrows that familiarity and turns a short spoken oui into a meme reply, circulating on soundboards under spellings like auclairdelalune. Its appeal online is less about the song itself and more about the unexpected, deadpan answer, which editors reuse in pranks, reaction videos and short edits where a plain yes would feel too ordinary to be funny on its own today.