![electron memory monitor electron memory monitor](https://i.ebayimg.com/images/g/Z5UAAOSwTY5gY9fy/s-l640.jpg)
The beam can be moved up by applying a positive voltage of the first plate, and can be moved down by applying voltage to the second plate.
![electron memory monitor electron memory monitor](https://i.ebayimg.com/images/g/FSMAAOSwm~pgY9fz/s-l640.jpg)
![electron memory monitor electron memory monitor](https://www.3bscientific.co.uk/thumblibrary/W44081/W44081_01_1200_1200_Electronic-Monitoring-Memory-and-Printer-Unit.jpg)
![electron memory monitor electron memory monitor](https://linuxhint.com/wp-content/uploads/2018/06/Stacer.png)
Now- a- days they are called as I-O devices, because both input and output devices are connected together and are dependent on each other.Monitor is the output device of the computer.Most of us spend a lot of time in front of our monitors, Let us know what is inside a computer monitor.