The melody comes from McDonald's 'I'm Lovin' It' campaign, which launched globally in 2003 with its famous five-note 'ba da ba ba ba' mnemonic. Rolled out across television, radio and in-store audio in more than one hundred countries, it became one of the most recognisable advertising jingles in the world. Online, the short sting spread as a meme sound for fast-food jokes, parody commercials and ironic luxury edits. It endures because almost everyone recognises it within a fraction of a second, making it perfect shorthand for burgers, fries and drive-thru culture.