Good composition is very important in photography yet is something that is hard to define
Ok, it's a cliché, but the only rule in photography is that there are no rules, but there are a number of established composition guidelines which can be applied in almost any situation, to enhance the impact of a scene.
These guidelines will help you to take more compelling photographs, lending them a natural balance, drawing attention to the important parts of the scene, or leading the viewer's eye through the image.
Once you are familiar with these composition tips, you'll be surprised at just how universal most of them are. You'll spot them everywhere, even in films and TV dramas, and you'll find it easy to see why some photos "work" while others feel like simple snapshots.