Light and shadow can be used compositionally to direct the viewer's eyes and to create interest. At times it can even create mystery. Look for the interaction between light and shadow. Here are a few examples:

The viewer's eyes first go to the light. They bounce between the spots with light. Later on they start seeing things in the shadows. This helps to keep the viewer's attention. The longer someone looks at an image the better the image.

There is no doubt what draws attention. The dark shadows help force attention where it belongs. There are no distractions. The light stands out the shadows hide distractions.

Once again only the ridge has light on it. The shadows are not dark but still they offer no competition to the lit ridge. There are many shots out there that can be had simply because of the interplay between light and shadow. Here is the last example for today:

Enjoy playing with light and shadow.