Light-emitting diodes are front and center for many of our digital experiences. Every modern phone and tablet you look at uses LEDs in its display. It’s worth knowing how these work. In short, LEDs ...

I’m something of a headlight nerd. In a previous life, I retrofitted HID projector headlamps onto my 2009 Honda Civic Si for better light output. I’m planning a similar project for my beater 2015 VW ...

They look otherworldly — like a Star Wars Stormtrooper’s helmet — and promise to give you clearer, smoother-looking skin. LED light masks are exactly what they sound like: devices illuminated by LED ...