Ions are charged particles that form when atoms gain or lose electrons. This process results in the creation of positively charged ions, known as cations, and negatively charged ions, called anions. Ions play a crucial role in various chemical reactions and are essential for the functioning of biological systems, such as nerve impulse transmission in humans. In solutions, ions can conduct electricity, making them vital in electrochemical processes. They are also key components in the formation of ionic compounds, which are formed through the electrostatic attraction between cations and anions. Understanding ions is fundamental in fields like biochemistry and materials science.