LCD stands for Liquid Crystal Display. It is a flat panel display technology commonly used in monitors, televisions, smartphones and tablets.

Just like LED (Light-Emitting Diode) and gas plasma technology, it makes screens much thinner than cathode ray tube technology. The biggest difference is that LCD consumes less power than LED. Because it works on the principle of blocking the light instead of spreading it.

The backlight on the LCD provides an even light source behind the screen, and this light is polarized. This means that only half of the light shines through the liquid crystal layer. Liquid crystals consist of some solid and a liquid substance that can be bent by applying an electrical voltage to them. It blocks polarized light when turned off, but reflects red, green, and blue light when turned on.

All LCD screens contain a matrix of pixels that displays the image on the screen. While the first LCDs had a passive matrix display that controlled individual pixels by sending a charge to their columns and rows, newer LCDs use active matrix technology incorporating film transistors. These transistors contain capacitors that allow individual pixels to actively hold their charge.