Scale is a simple concept. From a very early age, children know about big and small, heavy and light, more and less. Extreme scales, however, are another story.
Try to imagine, for example, the size of the universe… or $1 trillion made up entirely of dollar bills. Exactly. Grasping the actual quantities involved in extreme scales can be difficult, which makes managing scale in visualizations an interesting problem.
MORE: http://blog.visual.ly/12-visualizations-that-will-change-the-way-you-view-scale-in-your-world/
