I watch a lot of explaining videos, and Technology Connections makes some of the best. The host is knowledgeable, explains things clearly, and is funny, to boot. And this episode he talks about retroreflectors, which are reflective surfaces that send light back to its source with very little scattering. This is very useful for road [&]

https://boingboing.net/2020/08/31/how-road-sign-reflectors-work.html