Light- a form of energy, detectable with the eye, which can be transmitted from one place to another at finite velocity.
Visible light is a small portion of a continuous spectrum of radiation ranging from cosmic rays to radio waves.
White or visible light, that which the eye detects, is only a fraction of the complete spectrum - produced by shining white light through a glass prism.
Two complimentary theories have been proposed to explain how light behaves and the form by which it travels.
Waves have electrical and magnetic properties => electromagnetic variations.
Wave theory effectively describes the phenomena of polarization, reflection, refraction and interference, which form the basis for optical mineralogy.
Components of a Light Ray