Science 2.0: The LED turns 50 this year—and in honor of the occasion, researchers at General Electric’s Nela Park research lab in Cleveland, Ohio, interviewed the LED’s inventor, 83-year-old Nick Holonyak. The technology has taken off since 1962, when the first LED was capable of emitting only a low-intensity red light. Because the light output was not very high, LEDs were originally used as indicator lights in many devices. But they now span the visible, UV, and IR wavelengths with very high brightness, and their cost has dropped immensely. They are more efficient, last longer, and emit less heat than incandescent bulbs. In the interview, Holonyak, who continues to teach engineering at the University of Illinois at Urbana-Champaign, discusses the LED’s development and the importance of R&D in science and technology.