While this piece from Popular Science on the importance of the blue LED is a couple of years old, it’s definitely still worth a read.
Three scientists have jointly earned the Nobel Prize in physics for their work on blue LEDs, or light-emitting diodes. Why blue in particular? Well, blue was the last — and most difficult — advance required to create white LED light. And with white LED light, companies are able to create smartphone and computer screens, as well as light bulbs that last longer and use less electricity than any bulb invented before.