The signals would work like this: Red - Stop Yellow - Get ready for lights ... or humans through the junction. Once the light turns white, humans simply follow the car in front of them, which ...

including something very close to the warm yellow-white of a classic bulb. LEDs still have their share of issues—as I write this, the light in my apartment’s entryway is flickering erratically ...

behave differently to the green ones and the yellow ones and the red ones. They come out at a shallower angle, and that's why you get the full spectrum of colours from the white light of the sun.

Complementary colors live on opposite sides of the color wheel. Imagine red and green, blue and orange, or yellow and purple. Or move a half step over on the wheel, and combine a yellow-green color ...

You can use a prism to split (or disperse) white light into a spectrum of colours: red, orange, yellow, green, blue, indigo and violet. Dispersed means that the colours are separated out.