One of the visual elements in photography is backlit. With this visual element, the light comes towards the camera. while the shadows are at to the sides and bottom of the photo. This lighting, it makes an interesting view on the photograph. A great example of a backlit photograph is in this link.
http://www.worldpressphoto.org/photo/2012-alejandro-kirchuk-dls1-al?gallery=2634&photographer=2759&category=52
The central figure is backlit both by the lamp and the light coming from the window. It adds to the drama and the feeling of stress he must feel as a caregiver to his wife with Alzheimer’s disease.