Monitor type refers to the two types of monitors: CRT (Cathode Ray Tube) monitor and LCD (Liquid Crystal Display). A Cathode Ray tube is the picture tube that is used to create images in most desktop monitors. The CRT in a computer display is similar to the picture tube in a television receiver. It is the glass part of the computer monitor, which includes the screen also. CRT uses an electron gun to shoot the electron beams at the coloured phosphor dots that are inside the surface of the monitor screen. This causes the phosphor dots to glow and an image is produced. The LCD (Liquid Crystal Display) monitors form screen images using liquid crystals activated by electric fields.