Simply put, the rule of thirds is the idea of breaking your image into 9 equal parts with horizontal and vertical lines such as below. The four intersecting points are considered to be the strongest part of an image. They are also known as “power points” Some DSLR’S even have a grid such as below in the viewfinder to show where and how the image is located within the strongest lines.
After initially placing the couple in the center of the image, I then moved them to the right third.
Notice they are on the vertical line and they intersect the 2 strongest visual points of the image.
Below is the image without the grid.
Notice that not only is this image stronger based on a slight movement of my position for the thirds, the image also now has a beautiful leading line of the road leading you into the couple and then through the image. All I did was slightly adjust my position and a much more impactful image happened. Understand, the first image was a real photograph I took just working quickly. Then, I stopped myself and said……think about the leading line and rule of third here. That’s when I got this image which is now much stronger as it is in the right third and the road. is a natural leading line through the image.