Nocturnal creatures have no use for sunlight. They have large eyes to take in the dim and darkness of the world during the night time hours. They get their vitamins, minerals and whatever else they need from the diurnal creatures and plants they eat. Their bodily functions are not helped by the daylight hours in which they snooze away in the darkness of their burrows or caves.
We are diurnal creatures. We need the sunlight not only to survive, but also to feel well and healthy. In reasonable quantities, our bodies revel in the sunlight; it helps us with our ability to absorb certain vitamins. Sometimes life makes it so we are not able to get out in the sunlight as much as our bodies would like, either because of lifestyle or because of a long string of somber days. At times like this, our bodies may react to the lack of sunshine by putting us in somber, lazy, even depressed moods.
In the past, we have had no respite from the somber days, but technology has brought us a way to help our bodies get through. We now have multi spectrum or full spectrum lighting available that we can use anywhere. It comes so portable that you can carry it in your brief case or it can be a light that is installed in your home that you can bask under and read a book or just relax. This lighting is meant to have similar effects to the sun.