Introduction Radiation was discovered just slightly more than a century ago, with a profound effect on both industry and medicine. Several notable scientists were key in bringing radiation to the forefront. Methods Historical review of scientists who played key roles in the discovery of radiation and its use in medicine are reviewed. Results Wilhelm Roentgen, Henri Becquerel, and Marie and Pierre Curie's work is reviewed. The field of radiation safety was born to protect those handling radiation in addition to patients who received radiation for medical purposes. Conclusion Radiation use in medicine continues to evolve after notable discoveries by Nobel Prize-winning scientists.