Pocoyo began as a Spanish animated preschool series in 2005, following a curious little boy in blue and his animal friends in a simple, bright world. The XD part comes from the old text emoticon for laughing hard with eyes squeezed shut. Spanish-speaking meme pages combined that internet slang with Pocoyo clips and edits, turning a gentle children's show into shorthand for goofy, over-the-top laughter. The sound still circulates because the contrast is easy to read in any language and fits very short edits.