Visualization is easy, right? After all, it’s just some colorful shapes and a few text labels. But things are more complex than they seem, largely due to the the ways we see and digest charts, graphs, and other data-driven images. While scientifically-backed studies do exist, there are actually many things we don’t know about how and why visualization works. To help you make better decisions when visualizing your data, here’s a brief tour of the research.