When light hits a surface, some of it is absorbed, and some of it is reflected. There are two types of reflection;

1. SPECULAR REFLECTION – As we might imagine a mirror reflects, or a still lake or a polished gold bar. The surface is smooth and so a ray of light can be reflected like a rubber ball in a vacuum.

2. DIFFUSE REFLECTION -Happens due to ‘sub-surface scattering’. Certain wavelengths of light are absorbed, and others are re-emitted in random directions. Objects get their colour from the wavelengths of light they most strongly reflect.