Rule of ThirdsThe rule of thirds is that a photo is often more visually pleasing if the main features of the photo fall into thirds. So a landscape works well if there is a lower third, a middle third, and an upper third. A sunset should not have the sunset right at the center of the photo. There should be foreground in the lower third, the sunset at the middle third, and then sky in the upper third.
Thirds can also apply in vertical stripes. This is less common, but also a way to break your image into thirds.
Here are some examples of images that feature thirds.
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