Explanation :
The phenomena in which the ray of light bend towards or away from the normal is called the refraction of light. Light always travels in straight line. If the speed of light in both medium differs then refraction occurs.
According to Snell's law :

Where
and
is the refractive indices of two medium 1 and medium 2.
and
is the speed of light in medium 1 and medium 2.
Hence, the given figure shows the refraction of light.