A map, any map, is a picture of the world in miniature. They can be frighteningly complex, chock full of annotation and information, but they can and should be easy to understand.

A map may have a hundred or more words on it but it’s easy to tell what those words mean. When the name of the road is written on top of a drawing of that road there’s no doubt about what that name refers to. Beyond that, maps often show a number of roads, cities and geographical features that can be identified and compared to each other. Not only can we see where roads are and where they go, we can look at roads in the context of the world around them.

This ability to synthesize a large amount of data into an easy-to-read format is what makes the map one of the greatest pictorial displays of information people ever created. It’s rare that a picture is really worth a thousand words, but a good map is worth more than that.

Eduard Tufte, the man Business Week called the “Galileo of graphics,” highlighted a number of maps when giving examples of well executed visual information. Envisioning information is exactly what maps do. It would be difficult, if not impossible, to write out all the information that is visually displayed.

If you read: North Avenue is south of Armitage, which is south of Fullerton, which is south of Diversey it would be reasonable to ask, “But how far south of Fullerton is Armitage and for how long, when do they start, and do they run parallel the whole time?” With a map these questions don’t come up.

Like murals, maps put things into a larger context. The great murals of artists like Diego Rivera or ...