The tune began as a short phrase from Gran Vals, a guitar piece written by Spanish composer Francisco Tarrega in 1902. Nokia adopted it as a ringtone for its early mobile phones in the 1990s, and as those handsets spread around the world, the melody became one of the most recognised sounds on the planet. It later moved from pockets into pop culture, appearing in parodies, remixes and comedy videos that use it as shorthand for an old-fashioned phone call. Its simple, catchy shape is why it still works today.