Sleeping is one of the needs of people, to be able to rest and regain our strength. Sleeping at night is important to me since I have a work during daytime I only have my night hours to rest. Since I was a kid, my family was used in sleeping with lights off. Maybe because to reduce the electrical bill. As I grew older, I still have the habit of sleeping with lights off with a dark room. A slightest light will affect my sleep.
I am working most of the time in front of the monitor either on a laptop or desktop at work, so my eyes are always exposed to glare. A dark room at night will help my eyes well rested.
How about you, which do you prefer?