This article shows that polymers have become one of the most important parts of almost everything humans do. Polymer nanocomposites (PNCs) have been recognised as an efficient means of endowing materials with exceptional properties that would be impossible to attain with the components alone. Nanoscale polymer matrices and reinforcing phases constitute polymer nanocomposites (either organic or inorganic constituents). Various characteristics are used to divide polymer nanocomposites into distinct classesThis page discusses the preparation procedures. They include the sol-gel method, in-situ polymerization, solution mixing, melt mixing, and in-situ intercalative polymerization. Proteins (for example, soy, collagen, and fibrin gels), polysaccharides (for example, starch, alginate, and chitin/chitosan), and synthetic polymers such as poly(hydroxyl butyrate) (PHB), poly(lactic acid) (PLA), poly(glycolic acid) (PGA), and poly(caprolactone) (PCL) may have biomedical applications. These non-hazardous compounds are biocompatible and decompose at a rate that may be regulated. For biomedical applications, polymeric nanocomposites must overcome numerous challenges, including their manipulation and handling. Due to their high surface free energy, nanoparticles readily accumulate in the air and can be oxidised or contaminated. These miracles are capable of altering the antibacterial properties of nanocomposites containing metal nanoparticles. The amount of microbe surface area in contact with metal nanoparticles influences the nanoparticles' antibacterial activity. Nanoparticles can eradicate bacteria in a variety of ways due to their small size and high surface-to-volume ratio. Moreover, we have discussed the inherent properties of polymer matrices, the reinforcing effects of nanofillers, and the manufacturing processes.