By John Burn-Murdoch FT
The focus on understanding is because I see data visualisation as being fundamentally about conveying information to people. (John Burn-Murdoch)
Visualisation is merely a procedure, a way of using that middleman to communicate ideas that convey much more than just pictures of statistics. (p 224 HBR Goodchart)
To create effective charts, you have to understand how people consume charts