Electrochromic materials are substances that change color or opacity when an electric current is applied. This property allows them to be used in various applications, such as smart windows, which can adjust their tint to control light and heat entering a building. This technology helps improve energy efficiency and enhances privacy. The mechanism behind electrochromism involves the movement of ions within the material, which alters its optical properties. Commonly used in devices like smartphones and automotive displays, electrochromic technology is gaining popularity for its potential to create dynamic and responsive surfaces in everyday products.