Polymers, with their viscoelastic nature and complex molecular structure, significantly enhance oil recovery (EOR). This text elucidates the mechanisms underpinning their application in EOR, categorizing them into synthetic and natural (bio) polymers, each with distinct properties. A variety of EOR techniques employing polymers, like foam, alkali-polymer, surfactant-polymer, alkali-surfactant-polymer, and polymeric nanofluid flooding. Most polymers are pseudoplastic under shear, with biopolymers offering the benefits of salt resistance and thermal stability; however, plugging might result in the wellbore area, and they degrade. Despite its complexities, associative polyacrylamide shows promise, though hydrolyzed polyacrylamide remains the industry standard. Notably, alkali-surfactant-polymer flooding proves effective at various scales, and polymeric nanofluids hold potential for future EOR applications.