Effective uses of backlighting with digital photography. Samples follow: rim/hair lighting, emphasize translucence, & create a silhouette.
Rim/hair light – when light traces the outline of the subject.
Silhouette – high contrast. Subject is black and is set against a colorful lit background. Is recognizable by its outline alone and is not superimposed on other objects so that it blends with them creating a single shape.