It is used in the food, papermaking, textile and electronic industries, among others, peroxide is a great disinfecting and bleaching agent. It is clear and colorless, and when poured over an open wound, peroxide will kill many types of microorganisms. It's also an extremely stable compound — when properly stored. Many chemical compounds break down over time, and hydrogen peroxide is no exception. Although it is extremely stable, the solution can start to decompose when it comes in contact with light and heat. The brown bottle in your medicine cabinet is a bulwark against those two catalysts. Light cannot penetrate the tint of the brown bottle, preventing oxidation, which can result in an increase in temperature.