1. The angle of incident is equal to the angle of reflection.
2. The incident ray, the reflected ray and the normal lie on the same plane.
When a beam pass of parallel light rays is incident on a smooth and plane surface, the reflected rays will also be parallel. This type of reflection is called Regular Reflection.
When a beam of parallel light rays is scattered in all directions. Therefore the parallel rays incident on the surface will reflect in different directions. This is also called Diffuse Reflection.