That's all folks became the signature closing line of Looney Tunes and Merrie Melodies cartoons, traditionally spoken at the end of each short as the series logo appeared. Bugs Bunny, introduced in 1940, became the character most closely associated with the farewell, often munching a carrot while delivering it. The phrase spread beyond television into memes, video edits and reaction clips, where it works as a universally understood signal that a story is over. Its longevity comes from that simplicity: audiences recognise the ending instantly, even without seeing the cartoon itself.