I should preface this by saying I’m not with tech support.
 
So if you came here looking for help with your computer hardware, you found the wrong video.
 
But, please stay on the line. Your call is important to us. [hold music]
 
But seriously, if you’re wondering why your big ol’ boxy computer monitor broke after you stuck your Garfield refrigerator magnet to it, you’re dealing with some pretty old technology.
 
Most older computer monitors use cathode ray tubes, or CRTs -- it’s the same basic technology that was used in television for decades.
 
And it’s true that CRT monitors can get messed up by magnets pretty easily. 
 
That’s because they work by firing beams of electrons extremely precisely at millions of tiny phosphorescent dots on a glass screen. 
 
Hit a green dot with electrons, and it makes green light; hit a red one...red light; hit a blue one...blue light.
 
When you think about it, it’s pretty remarkable that we figured out how to use this system to make color TV for 50 years. 
 
But we managed to do it by controlling those electron beams with magnets.
 
Because remember: Electricity and magnetism are both manifestations of the same force -- electromagnetism -- so we can push and pull electrons around using magnetic fields. 
 
SO! If you stick a magnet on a CRT screen, or even its outer case, it’ll interfere with the magnets at work inside, causing the electron beams to miss their marks.
 
So instead of seeing your snazzy business presentation, or your term paper on the works of Tom Clancy, you’ll see psychedelic distortions and random splashes of color.
 
I mean, it's pretty cool to watch, but less cool is the fact that the phosphorescent material on the glass gets permanently magnetized, which means your screen will become permanently damaged. 
 
So maybe don't do that unless you really don't care about your monitor anymore. 
 
And if that IS what you’ve managed to do, well then, HEY! Now you can finally upgrade your monitor!
 
Welcome to the 21st century!
 
Thanks to our friends on Tumblr for asking about this! And thanks, too, to our Subbable subscribers who keep these answers coming.
 
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