A monochrome monitor is a computer display system that only shows one or two different shades of color on the screen. Early computer monitors were typically of the monochrome type before the introduction of color monitors during the 1980s. As of 2015, monochrome monitors are rare to find.
Colors that are displayed in a monochrome monitor depend on the type of phosphorus used inside the display tube of the monitor. Generally, monochrome monitors use a green color display; however, a few monitor types also include white and red colors. Monochrome displays were also used in other devices, such as laboratory equipment, information kiosks and cash counters.