In photography & Graphic, the rule of thirds is a type of composition in which an image is divided evenly into thirds, both horizontally and vertically, and the subject of the image is placed at the intersection of those dividing lines, or along one of the lines itself.
while creating a rule of thirds is dividing your frame into nine equal rectangles. You can do this by creating two vertical and two horizontal lines. The four lines will intersect at four points. These are the points where your point of interests should be