Light is the electromagnetic ray that the human eye can see. Or another definition of light is electromagnetic radiation, whether it is with visible wavelength or not. While objects that emit light are called light sources. and the light I'm discussing here may be the illuminating light, the cigarette lighter, and the hp. I see the uniqueness of the light.
http://www.pengertianku.net/2015/06/pengertian-cahaya-dan-sifatnya-serta-contohnya.html
Read next
From @andisantos