Ionization is the process by which an atom or molecule gains or loses electrons, resulting in the formation of charged particles called ions. This can occur through various means, such as exposure to high-energy radiation or collisions with other particles. Ionization plays a crucial role in many natural phenomena, including lightning and the behavior of gases in the atmosphere. In practical applications, ionization is essential in fields like chemistry and medicine. For instance, mass spectrometry utilizes ionization to analyze the composition of substances, while radiation therapy employs ionization to target and destroy cancer cells. Understanding ionization helps scientists manipulate matter at the atomic level.