Line
Lines have many uses in a photograph. They can divide, unify, or accent certain parts of a composition. If they are interesting enough, they can become a visual topic in themselves: Stay alert to catch transient lines, like shadows or shafts of light, before they disappear. Lines lead the eye into a scene. Leading lines are most effective when there is some relation between line and subject, such as winding stone steps leading to a castle door. You can exaggerate their impact further by using a wide-angle lens and finding a vantage point close to the beginning of the lines—kneeling to get close to train tracks, for example. Line forces the viewers eye to follow it to view the image.