The Z- Axis, An Exploration of Depth in Design - Texture

Adding a sense of depth to a design can make that design seem more realistic and increase visual interest. Building out the 3rd dimension pulls the viewer into the design and can help you set up entry points and control flow throughout your design.

We're 3-dimensional beings. Objects around us exist in 3 planes, but on screen we work in only 2 of them. The lack of the one dimension means our compositions appear less than lifelike. Adding back the illusion of the missing dimension will add back a sense of reality,ﾊa sense of the physical.

(Bradley, Steven, 11 Ways To Add Depth To A Design, 2012, http://www.vanseodesign.com/web-design/pictorial-depth-cues/)

What is depth?
* Depth is the creation of something more than what is required or minimal.
* Depth is something which seems arbitrary, but which you are sure has some reason.
* Depth is the hidden, the unclear, the difficult, the different.
* Depth is abundance and sometimes refinement.
* Depth is theatre and ritual.
* Depth is meaning.

.... more at http://z-axis.cenk.it/