Lines are optical phenomena that allow the artist to direct the eye of the viewer. 

The optical illusion of lines do exist in nature, and visual arts elements can be arranged to create this illusion. 

The viewer unconsciously reads near the continuous arrangement of different elements and subjects at varying distances. 

Such elements can be of dramatic use in the composition of the image. 

Lines can also derive from the borders of different colors or contrast or sequences of discrete elements. Subject lines contribute to both mood and linear perspective, giving the viewer the illusion of depth. 

Oblique lines convey a sense of movement, and angular lines generally convey dynamism and possibly tension. 

Lines can also direct attention towards the main subject of the picture or contribute to the organization by dividing it into compartments. 

Many lines without a clear subject point suggest chaos in the image and may conflict with the mood the artist is trying to evoke. 

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