Stain repellent is a type of treatment applied to fabrics, surfaces, or materials to prevent stains from setting in. It works by creating a protective barrier that makes it difficult for liquids and dirt to penetrate the material. Commonly used on clothing, upholstery, and carpets, stain repellents help maintain the appearance and longevity of items by making them easier to clean. These products often contain special chemicals that repel water and oil-based substances. Popular brands include Scotchgard and Teflon, which are known for their effectiveness. Stain repellents are especially useful in households with children or pets, where spills and messes are more likely to occur.