Cations are positively charged ions that form when an atom loses one or more electrons. This loss of negatively charged electrons results in an overall positive charge, making cations essential in various chemical reactions. Common examples of cations include sodium Na+, potassium K+, and calcium Ca2+. Cations play a crucial role in many biological and chemical processes. In living organisms, they help regulate nerve impulses and muscle contractions. In chemistry, cations interact with negatively charged ions, known as anions, to form neutral compounds, such as table salt NaCl, which consists of sodium cations and chloride anions.