The document discusses the rule of thirds in photography composition. It explains that the rule of thirds involves imagining a 3x3 grid over an image and placing points of interest along the lines or intersections. Studies have shown that the human eye is naturally drawn to these points. Examples show how positioning a subject's eyes or a landscape horizon along these lines can improve composition. Learning to identify points of interest and intentionally place them is important for both shooting and post-production cropping.