A display device is an output device that visually presents text, images, or video from a computing system, typically by arranging pixels on a screen to form the desired content, and may also incorporate input capabilities in touch-enabled variants.[1]

Display devices have evolved significantly since the early 20th century, with cathode ray tube (CRT) technology serving as the foundational type, using electron beams to excite phosphors on a screen for image formation.[2] Modern displays predominantly employ flat-panel technologies, including liquid crystal displays (LCDs), which use liquid crystals to modulate light from a backlight through polarized filters; light-emitting diode (LED) arrays that directly emit light without a backlight; and organic light-emitting diode (OLED) panels, where organic compounds generate light via electroluminescence for superior contrast and flexibility. As of 2025, LCDs dominate mass-market applications due to cost and scalability, while OLEDs lead in premium segments for better image quality.[3][4] While CRTs offered excellent color accuracy and viewing angles, their bulkiness and high power use led to their obsolescence by the early 2000s, with LCDs dominating due to thin profiles and energy efficiency, though OLED and advanced LED variants like quantum-dot-enhanced models now provide deeper blacks and wider color gamuts in premium applications.[3][2]