Chloride is a common and highly stable inorganic anion with the chemical formula $\text{Cl}^-$. As a major electrolyte, it plays a fundamental role in maintaining fluid balance and electrical neutrality within biological systems. In physiology, the movement of chloride ions is critical for establishing and propagating electrical potentials across cell membranes, processes that underlie nerve impulse transmission and muscle contraction. Furthermore, chloride concentration is essential for maintaining osmotic balance in blood and interstitial fluids. Chemically, it readily dissociates in water, contributing to the conductive properties of aqueous solutions and serving as a principal component in various salts and chemical formulations.