Electromagnetic radiation (EMR) is a type of energy that travels through space and matter in the form of waves or particles. EMR can have different frequencies and wavelengths, which determine its properties and effects on matter. EMR can interact with electrically charged particles, such as electrons and protons, and cause them to move or vibrate. This can result in the production of heat, light, or chemical reactions. EMR can also affect the structure and function of living cells, especially the DNA, which carries the genetic information.