Final answer:
A mirror reflects light by following the law of reflection where the angle of reflection equals the angle of incidence, resulting in light being reflected at specific angles. This behavior allows for clear mirror images to be seen and enables mirrors to direct light in predictable paths.
Step-by-step explanation:
A mirror affects the path of light primarily through the process of reflection. According to the law of reflection, when a light ray strikes a mirror, which has a smooth surface, the angle of reflection is equal to the angle of incidence. This means that light rays are not scattered randomly as they would be with a rough surface, but rather reflected at specific angles, enabling us to see clear mirror images. This reflection is why we can see ourselves in a mirror or why a mirror can redirect a laser beam in a straight, predictable path.