A display device is an output device for displaying information in text or image format. Output devices provide a way to display information to the outside world. These devices must be controlled by other external devices for the information to be displayed correctly. You can control these displays by connecting them to a controller. Some displays can only show numbers and alphanumerics. Some displays can display images and all kinds of text. The most commonly used displays with microcontrollers are LEDs, LCDs, LCDs, and 7-segment displays.