To appreciate the scale of cosmic dimensions and distances, we can translate them into smaller scales that are more familiar to us. For example, if Earth were imagined as the size of a ping-pong ball, the distance to Mars would be comparable to the length of a football field. Other familiar scales can be used in the same way.
We are all familiar with the idea of a pixel. The source quotes Wikipedia's definition: in a digital image, a pixel is the smallest structural element of the image and is sometimes described simply as the smallest point making up an image.1
Now imagine that the diameter of the Moon were represented by the width of a single pixel on your screen. At that scale, we could model our Solar System in an illuminating way. This was the idea of visual-effects artist Josh Worth, who used it to illustrate cosmic dimensions in a form his five-year-old daughter could understand.2
1 If you look very closely at your screen, you may just barely be able to distinguish its pixels. [source]
2 Even at this tiny scale, you would need an extremely long display to see all the planets of the Solar System at once. Fortunately, the window's scrollbar solves that problem for us.