LCD screens use liquid crystals to control the polarization of light and display images. They consist of millions of pixels made up of red, green, and blue sub-pixels. When voltage is applied to the liquid crystals, they twist polarized light, allowing it to pass through filters and be seen by the human eye. LCD screens work by varying the intensity of the red, green, and blue sub-pixels to trick the brain into perceiving different colors, even though it only sees light of the three primary colors. LCD displays are used widely in computer monitors, televisions, and other electronics.