How is white made on a computer screen?

In print, white is a lack of color, but on a TV or computer monitor, the opposite is true. Additive color on monitors is created by mixing red, green and blue light—referred to as RGB. Two additive primary colors produce a secondary color: red and blue make magenta, red and green make yellow, blue and green make cyan. Where all three overlap—voilà—white. Turn the colors off and you have black. The dark type you are reading here is where the red, green and blue screen pixels are turned down/off. The white background is the result of all three colors being on.