A lens is a transparent object, usually made of glass or plastic, that bends light to focus or disperse it. Lenses are commonly used in everyday items like glasses, cameras, and microscopes. They can be shaped in various ways, such as convex (curving outward) or concave (curving inward), which affects how they manipulate light. When light passes through a lens, it changes direction, allowing us to see clearer images or magnify small objects. For example, a convex lens can make distant objects appear closer, while a concave lens can spread light rays apart. This property of lenses is essential in many optical devices.