Question

deffine source of light and its 2 type

Answer 1

A light source essentially is an optical transmitter that is paired with an optical receiver, both of which are connected to electrically based devices or systems. So, the source converts electrons to photons and the detector converts photons to electrons.

The sun is the most important source of light. The stars and moon are also natural forms of light. Artificial light is light made by humans, for example candles, fire and oil lamps. The electric light is now the most convenient form of artificial light.

Answer 2

Any thing which produces light can be said as a source of light. There are two types of sources of light. They are:
1)natural
2)artificial