A mirror is a smooth, reflective surface that bounces back light, allowing us to see our own image. Most mirrors are made of glass coated with a thin layer of metal, usually silver or aluminum, which enhances their reflective properties. They come in various shapes and sizes, from small hand mirrors to large wall mirrors, and are commonly used in homes, bathrooms, and vehicles. Mirrors have been used for thousands of years, with the earliest examples made from polished stone or metal. Today, they serve not only practical purposes, such as grooming and decoration, but also artistic and scientific functions, including in telescopes and lasers.