Blue (Da Ba Dee) was released in 1998 by the Italian eurodance group Eiffel 65 and became a worldwide number one hit the following year, defining the sound of late nineties dance music. Its nonsense-syllable chorus made it endlessly quotable, and the track lived on through early internet memes, ringtones and parody videos. A fresh wave of TikTok edits in the 2020s pushed the hook back into viral circulation, and it remains a go-to audio cue for anything blue, nostalgic or cheerfully absurd.