This study was conducted with the aim of production and designing of selfstudy educational content about the history of X-ray discovery and developing its related spectroscopic methods. This is a library research and indexing has been used as data gathering tool. It was found that in the 19 th century, many scientists were interested in studying the passage of electricity through solids, liquids, gases and vacuum, and cathode ray was discovered in the margins of these studies. Many experiments were then carried out to investigate the nature of cathode ray, and in 1895, when the range of this ray was examined in the air, X-ray was accidentally discovered. Physicians were amazed at the nature of X-rays and used them to study the structure of crystals and atoms, and physicians used them to study the human body and to diagnose and treat diseases. In 1896 the intensity of these rays was measured. In the years 1905-1909, characteristic X-rays were discovered and studied. Their electromagnetic nature was then proved by experiments. In 1913, these beams were used as the standard method for identifying crystals. In the 1920s, new spectrometers were developed to measure and detect the structure of matter, and in 1956, X-ray spectroscopy revealed the spiral structure of DNA strands in cells.