You’ve probably heard of light-emitting diodes, a type of energy-efficient light ... lead and exit through the negative lead in order for the LED to work. Circuit diagrams like the one below are used ...

Kids love building electric circuits, but connecting light bulbs to batteries with fiddly wires is tricky for young hands. Play dough and light-emitting diodes (LEDs) solve the problem beautifully.

The filament lamp is a common type of light bulb. It contains a thin coil of wire called the filament. This heats up when an electric current passes through it and produces light as a result.

In 1962, when he was 33, the scientist Nick Holonyak, Jr., created the first practical visible light-emitting diode. At GE, they called it "the magic one." Someone actually wrote that on the back ...