Ionization is the physical process by which an atom or molecule attains an electrical charge by losing or gaining one or more electrons. This transfer of electrons results in the formation of ions, which carry a net positive or negative charge, respectively. This process requires the input of sufficient energy, typically provided by high-energy electromagnetic radiation, such as ultraviolet light or X-rays, or through collisions with charged particles like electrons. In the field of plasma physics, ionization is fundamental, as it describes the creation of plasma—a state of matter consisting of an ionized gas. Ionizing radiation is utilized in various technologies for material analysis, medical imaging, and atmospheric detection, and it is also critical for understanding chemical reactions that occur in high-energy environments.