A computer monitor is an output device that is used as an electronic visual display for computers. This device allows the user to view program operations. With a mouse, the user can visually control program operations on the monitor.
Cathode ray tube and liquid crystal display are the two types of computer monitors. Modern computers use liquid crystal displays. These displays are thin, light and energy efficient.
Cathode ray tube monitors were popular from the beginning of the personal computer era in the 1980s until the early 2000s. These monitors are large and heavy and use more electricity than liquid crystal displays.