The visual world we observe every day is made up of, primarily, points, lines, and planes. These are the base components of design. Any combination of these elements can result in typography, blueprints, patterns, diagrams, etc.
This red plastic cup is an object that most people are familiar with but, it may have taken you a second to recognize what it was because of the angle I took the picture from. That being said, I’m sure it was the first object your eye recognized in this image. Our eyes are naturally drawn to points. They mark points in space. A point can be a visible thing or it can be the lack of something like the holes in the boards in my image.
As the eye follows multiple points in a row it forms a line. Lines have a certain length, but no specific breath. The lines in the grain of this piece of wood are continuous and could be measured, but are not wide enough to be considered planes. The viewer’s eye likely picked one of the more prominent lines and followed it around in a circle.
In this next photo, the blinds use individual planes to block out most light from the other side of the window when they are vertical. The individual strips can be measured in length, but because they can also be measured in breath or width they are considered to be planes. These planes are outlined by thin strips of lights seeping through the cracks which are negative space. The eye sees them as planes unless the wand is twisted and the planes lay flat and let in the light from outside.
This last picture demonstrates how scale can affect how we perceive things. We know that a quarter is not actually the size of the head of a fan, but at first glace, it looks like it’s larger.