Superoxide dismutase (SOD) is an important enzyme found in nearly all living organisms. Its primary function is to protect cells from damage caused by reactive oxygen species, specifically superoxide radicals. These radicals are byproducts of cellular metabolism and can lead to oxidative stress, which is linked to various diseases and aging. SOD works by catalyzing the conversion of superoxide radicals into less harmful molecules, such as hydrogen peroxide and oxygen. There are several types of SOD, including copper-zinc SOD, manganese SOD, and iron SOD, each varying in structure and location within the cell.