A person in a dark room looking through a window can clearly see a person outside in the daylight, whereas the person outside cannot see the person inside. Why?

A person in a dark room looking through a window can clearly see a per

1.	A person in a dark room looking through a window can clearly see a person outside in the daylight, whereas the person outside cannot see the person inside. Why?
Answer» There is usually some reflection that occurs at an interface between the two materials but most often of light passing through. Imagine you are inside in the dark. A person outside in bright sunlight is sending out (reflection) lots of light, most of which would come through the window to you, so you see them clearly. Since it is so bright outside, there is also a good amount of light which reflects back towards them. This can distract them from little bit of light from you that is going towards them, so they have much harder time seeing you.