Ambient Light- Ambient lighting is a photography technique which uses available or existing light in a scene.  It’s light that is independent of any light supplied by the photographer.

Tip: If using dim ambient light, the use of a Tripod is extremely encouraged to avoid unnecessary shake which will cause images to be blurry.

This photo was taken from the John Hancock building in Chicago.  The use of ambient light was required, as the use of a flash would have created a harsh reflection from the window.

Do you have a great example of ambient light?  Link to a photo in the comments section!