Scooby-Doo first appeared in Scooby-Doo, Where Are You! in 1969, created by Hanna-Barbera, with Don Messick as his original voice. His speech impediment, adding R sounds to words, and his distinctive giggle became trademarks across decades of series and films. The Rehehehe laugh spread online through cartoon clips, remixes and soundboards, detached from any single episode. Because viewers grew up hearing it whenever Scooby was scared, hungry or pleased with himself, the short clip now works as instant shorthand for goofy, nervous laughter in memes.