Hopper, Nighthawks

I think this is a very tragically poetic and simple painting, a picture of aloneness. Outside the building, there is no sign of life or activity. It is dark, and all the other shops have closed for the night. There are no cars either.
Inside, while there is still light, it is a harsh, impersonal light, not the warm glow of a home. The counter separates the bartender from the other people, and they are separated from each other.
The bright light of the "aloneness" building spills out onto the street and pervades the building in the left corner of the painting. Even though they are physically together in one location, they are still alone.