Filter media are materials used in various filtration systems to remove impurities from liquids or gases. They can be made from different substances, such as sand, activated carbon, or synthetic fibers, depending on the application. The primary function of filter media is to trap particles, contaminants, and pollutants, ensuring cleaner output. In water treatment, for example, sand filters are commonly used to eliminate sediment, while activated carbon filters help remove chemicals and odors. In air purification, HEPA filters utilize fine fibers to capture allergens and dust. Overall, filter media play a crucial role in maintaining the quality of air and water.