Composition
Composition is the skeleton of a picture: how areas, lines and forms are arranged to guide the eye.
A picture can be symmetrical and calm or asymmetrical and tense. Diagonals create movement, horizontals stillness and verticals dignity. Baroque painters built their pictures on dramatic diagonals, while the Renaissance preferred triangles and symmetry.
Many pictures follow rules of proportion such as the rule of thirds or the golden section, placing important lines and objects roughly a third of the way into the picture. It is seldom exact – but the eye often perceives such pictures as balanced.