A reflection is the appearance of an image in a mirror. When light strikes a surface, it reflects. When light is unable to penetrate through a surface, it bounces off or reflects. The majority of surfaces absorb and reflect some light. Mirrors, on the other hand, reflect nearly all of the light that strikes them, which is interpreted or read by your brain as an image of oneself in the mirror. The reflection is caused by the metallic coating on the rear.