Tannins are complex polyphenolic compounds naturally found in plant materials, such as bark, leaves, and fruit skins. Chemically, they are known for their affinity to proteins, a property that causes precipitation when mixed, which is the basis for their use as astringents in both industrial and natural applications. This interaction with proteins allows them to stabilize solutions and is critical in the process of converting hides into durable materials. Beyond this chemical function, the compounds also possess significant antioxidant capabilities, contributing to their biological roles. The chemical makeup and resulting properties of tannins have led to their study in biochemistry, material science, and medicinal phytochemistry.