How do computers keep time?

My first laptop lost track of time, so that got me thinking: how do computers keep track of time? Can they do it forever? And why don't they lose track of time when we turn them off?

Turns out the answer is a combination of processor, quartz crystal and the internet. They all work together to keep time.


This video wouldn't be possible without the work of others. Here are the sources I've used during my research & script writing:

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