We often teach in data analysis courses that one should look at the data before beginning any serious modeling endeavor. Indeed, visualization and modeling should go hand in hand. Each can inform the other and each process is enriched by the use of the other. Judicious use of graphics can save the practitioner from trying to fit overly-complicated models, while at the same time opening a window on interpretation. The power of simple plots as a tool for learning about moderately complex data structures is demonstrated via example.