Alternatively referred to as a video display terminal (VDT) and video display unit (VDU),a monitor is a video display screen and the hard shell that holds it. In its most common usage, monitor refers only to devices that contain no electronic equipment other than what is essentially needed to display and adjust the characteristics of an image.
Like most early TVs, the early computer monitor’s have a CRT (Cathode Ray Tube) that is found inside. Today, most users have replaced the traditional CRT monitor with the newer flat panel displays like that shown in the picture on this page.
Monitor is a term to describe the process of viewing or watching over someone or something.