How Concert LED Wristbands Work

In my last post about the Karol G concert, I wondered how the Cyalume (LED Wristband) works. And I found the answer.

Though I prefer NYT to WSJ, I believe WSJ has been doing great work on their YouTube channel. The beauty of its videos is the short playtime: 5 ~ 7 minutes. When I was in graduate school, my professor mentioned that when the core content is identical, the best book is often the thinnest one. This principle can also be extended to the realm of videos. Conveying something succinctly holds its own beauty. It is truly so.