Abstract
Wilhelm Röntgen discovered X-rays over 100 years ago in Wurzburg, Germany. Like many contemporary physicists, he was studying what happened when energetic electrons were made to hit a target inside a vacuum tube. While Röntgen himself coined the "X" for unknown, the mysteries of these "Röntgen rays" were quickly unravelled and harnessed for medical purposes. Imaging the human body with X-rays is now one of a suite of methods used to detect disease, and, specifically, to identify malignant disease or cancerous tumours. Generations have now benefited from the ability to see inside the human body effortlessly, painlessly and – at least in more recent years – almost instantaneously. As well as detecting disease, X-rays also provide the means for treatment: radiotherapy.