Alginic acid is a naturally occurring hydrophilic polysaccharide extracted from the cell walls of brown seaweed (Phaeophyceae). It is a linear copolymer composed of β-D-mannuronic acid and α-L-guluronic acid units linked by 1,4-glycosidic bonds, forming a high-molecular-weight polymer. This compound is widely used in the food industry as a thickening agent, stabilizer, and emulsifier in products like ice cream, sauces, and beverages due to its ability to form gels when exposed to divalent cations such as calcium ions. In pharmaceuticals, it serves as a disintegrant in tablets and a wound dressing material because of its biocompatibility and water-absorbing properties. Alginic acid is also employed in biotechnology for encapsulation and in wastewater treatment for metal ion adsorption. Physically, it appears as a white to yellowish powder that is odorless and tasteless, with a high viscosity when hydrated. Chemically, it is stable under acidic conditions but can depolymerize at high pH or temperatures. Its gelling properties make it valuable in texture modification, and it is considered a safe, renewable resource. Research from sources like PubChem and ECHA highlights its role in controlled drug release systems. Overall, alginic acid's versatility stems from its anionic nature and ability to interact with various ions, making it essential in food, medical, and industrial applications, with ongoing studies exploring its potential in nanotechnology and environmental remediation.