Composition is the arranging of elements in a work of art.
That could be music, painting, drawing, illustration, film, photography…
In photography the Rules of Composition are a set of rules and guidelines that help to create stronger images
Images that are well composed are more likely to be good images.
They help us to get the person looking at the images (viewer / audience) to look where we want them to
The Rules of composition are guidelines, sometimes breaking the rules can make the strongest images. However, they provide an excellent framework and starting point for creating strong images, particularly when you are first starting out in photography.