Tokyo, Japan :photo by Masashi Wakui
*night lights - moonscapes, dusk skyline, traffic, fair, etc.* Nailing Night Exposures: Here's a guide to the rough settings you're likely to need for popular low-light subjects.
Self-portrait of the photographer, Travis Burke, shooting the Milky Way under Utah’s Delicate Arch, with a little creative lighting from a flashlight. Camera settings: 50 sec., ISO Photo by Travis Burke
slow shutter speed is also used for light trails and light painting
Long exposure photo of traffic lights at night. In my opinion, it is a beautiful shot as it sheds colourful light upon a dark street.
Take the Best Nighttime Photo of Your Life - Night Photography Tips