Designing Interfaces, 2nd Edition

Chapter 7. Showing Complex Data: Trees, Charts, and Other Information Graphics

Information graphics—including maps, tables, and graphs—communicate knowledge visually rather than verbally. When done well, they let people use their eyes and minds to draw their own conclusions; they show, rather than tell.

These are my favorite kinds of interfaces. However, poor tools or inadequate design can sharply limit what you can do with them, and many information-rich interfaces just don’t quite work as well as they could.

The patterns in this chapter will help you make the best of the tools you have, and introduce you to some useful and interesting innovations in interactive information graphics. The ideas described in this introduction can help you sort out which design aspects are most important to you in a given interface.

The Basics of Information Graphics

Information graphics simply means data presented visually, with the goal of imparting knowledge to the user. I’m including tables and tree views in that description because they are inherently visual, even though they’re constructed primarily from text instead of lines and polygons. Other familiar static information graphics include maps, flowcharts, bar plots, and diagrams of real-world objects.

But we’re dealing with computers, not paper. You can make almost any good static design better with interactivity. Interactive tools let the user hide and show information as she needs it, and they put the user in the “driver’s seat” as she chooses ...