Lens Flare

Lens flare can be a cool thing. Not always, but sometimes.

It happens when the camera is pointed towards the subject who happens to be backlit by the sun or whatever the main light happens to be. Certain lenses are more prone to getting lens flare than others. Manufacturers place special lens coatings on the glass to help reduce it. You can also use a properly designed lens shade to help cut it down too.

But as you can see in this image, the flare actually makes the shot look good! It adds something to the interest of the overall image. The sun at the upper right streaming into the shot creates interest, but the circles caused by the lens itself completes the effect.