Final answer:
The rule of thirds in photography suggests placing the main subject at the intersections of the gridlines to create a visually balanced and interesting photo.
Step-by-step explanation:
When using the rule of thirds in photography, the best place to put the main subject is at one of the intersections of the gridlines. This technique helps to create a photo that is more balanced, interesting, and pleasing to the eye, compared to simply placing the subject in the center of the frame.
To apply the rule of thirds, imagine that your image is divided into nine equal segments by two equally-spaced horizontal lines and two equally-spaced vertical lines. The important compositional elements should be placed along these lines or their intersections. Many digital cameras offer a feature that overlays this grid on the screen to assist photographers in employing this compositional method.