Refract is a term used to describe the bending of light when it passes through a medium such as glass or water. When light passes through a medium, it changes direction and is refracted. This phenomenon is known as refraction. Refraction occurs when the speed of light changes as it passes from one medium to another. The angle at which the light is bent is determined by the index of refraction of the medium. Bending, in this context, is the process of changing the direction of light as it passes through a medium.