A computer display unit is a device that displays information in the form of text, images, and videos. The most common type of computer display unit is a monitor, which uses a technology called pixels to display the information. Pixels are tiny dots of color that are arranged in a grid pattern to create an image. Each PIXEL is made up of three colors: red, green, and blue. By combining these colors in different ways, a monitor can create a wide range of colors and shades.