Ever since philosopher and mathematician René Descartes first set quill to paper to draw a line on his newfangled “Cartesian plane” in the 17th century, people have sought ever-cleverer ways to represent data in a pictorial format. The reasons are obvious: A graph, chart, gauge, or map can, at a glance, show important features and trends of a data set that you might miss by poring over tables of numbers. It’s the reason why Edward Tufte’s The Visual Display of Quantitative Information is still considered the bible of data visualization almost 40 years after its first release, and why firms large and small are demanding software “dashboards” showing the real-time health of their businesses.