It is summer. It is hot. And it is time for sunburns. In my classes, I talk a lot about skin (anatomy and biology) and about UV rays (physics). This infographic from David McCandless and Information is Beautiful sums up what anyone should know about sunscreen. It is important information, especially for me who has skin so white it almost shimmers in the sunlight.
The picture is quite long, but you will not be disappointed when you get to the end. Enjoy!