Difference in between primary source of light and secondary source of light in easy way !!!

Here we know about the distinguish/ difference between primary source of light and the secondary source of light.

Primary source of light

i) The primary source of light is a real source of light.

ii) Primary source of light sends out primary waves in the all possible directions.

iii) The primary source of light is effective at every point on it's surface.

iv) The primary source of light is situated in the air.

The secondary source of light 

i) The secondary source of light is a fictitious source of light.

ii) The secondary source of light sends out secondary waves only in the forward direction.

iii) The secondary waves is effective only at the points where it touches the envelope.

iv) The secondary source of light is situated on the wavefront.

THE END