To understand Scattering, let's do a Small Experiment
Let's take a Laser, and two glasses. One has Sugar Solution (Sugar + Water), and the other has just water.
While passing laser light through the glass, we observe that we cannot see the Ray of Light in both Sugar Solution and Water
Now, in Water, we add milk and Stir it
We now observe that we can see the Ray of Light in the Milk + Water glass.
This is due to Scattering of Light
The milk particles in the Second Glass are big enough to scatter light, and thus we see the Ray of Light in the 2nd Glass
Now, we can Define Scattering of Light
Definition of Scattering of Light
Scattering of light means throwing of light by particles in all possible directions
Did you notice that this Scattering of light is not done by all particles?
There are Sugar particles in the Sugar Solution, but they are very small... so they don't scatter light.
Whereas, the milk particles in Milk are big enough to Scatter light
Now, lets look at a few applications of Scattering of Light