The rule of thirds is a compositional guideline in photography that breaks an image down into thirds, both horizontally and vertically, so you have nine pieces and four intersection points. The idea is to place the subject of the image at the intersection of those dividing lines or along one of the lines itself. This technique helps to create a pleasing, well-balanced image by giving the main point of interest special emphasis, marking it as important. It feels natural and harmonious, whereas placing the main subject in the center of the image can feel static and uninteresting. The rule of thirds is widely considered to be one of the most important first techniques you can learn to create better compositions and help you progress from "taking pictures" to "making photographs". While it is a fundamental principle of photography, it is also okay to break the rule of thirds.