Unity is the harmony or agreement between all the parts of the composition that is apparent to the eye. The whole is predominant over the parts.

In unity by repetition the artist repeats an element, a size, a shape, a texture, and a color or motif.

When the artist continues something, usually a line, an edge, or a direction from one object to another. The viewers eyes are smoothly carried from object to object by the placement of the objects.

Unity of variety is repeated by the artist using the same elements but in varied colors, sizes , and values.

Objects of a composition don't look unified because there is no repetition, continuation, or proximity. The knowledge of the composition are known to go together by knowledge of the objects.