Discovered in the 1870s, X-rays were a medical miracle, allowing doctors to see inside a living body.
The first use of X-rays under clinical conditions was by John Hall-Edwards in Birmingham, in January 1896, when he found a needle stuck in the hand of a friend.
Despite the radiation dangers of X rays, manufacturers were quick to capitalise on them. By the 1930s, most UK shoe shops featured large X-ray machines - Pedoscopes - with which customers could watch their toe bones wiggling inside their shoes.
Today, magnetic resonance imaging (MRI) scans are the latest technology.