Oxidative phosphorylation is a metabolic pathway that occurs in the mitochondria of eukaryotic cells. It is the process by which ATP, the energy currency of the cell, is produced through the oxidation of nutrients such as glucose and fatty acids. This process involves the transfer of electrons along a series of protein complexes in the inner mitochondrial membrane, ultimately leading to the production of ATP through the action of ATP synthase. Oxidative phosphorylation is a crucial aspect of cellular respiration and energy production in eukaryotic organisms.