Nyan Cat began in 2011 as a short animated GIF of a grey cat with a Pop-Tart body flying through space and leaving a rainbow trail. Paired with a fast, cheerful Japanese pop tune, the clip was uploaded to YouTube and quickly became one of the internet's most recognisable memes, spawning remixes, games and merchandise. Its simple, joyful absurdity helped it survive long after many viral trends faded, and creators still use tiny bursts of its melody as instant shorthand for internet nostalgia, silliness and playful chaos.