Activated carbon filters are devices that use activated carbon to remove impurities and contaminants from air or water. The activated carbon is a form of carbon that has been treated to create a vast network of tiny pores, increasing its surface area. This allows it to effectively adsorb (not absorb) various substances, including chemicals, odors, and pollutants. These filters are commonly used in various applications, such as in water purification, air filtration systems, and aquariums. They are effective at improving the quality of air and water by trapping harmful particles, making them a popular choice for both residential and industrial use.