Excursus: Booting Up

If you’ve been around computers for any length of time, you’ve heard the terms reboot or boot up used in connection with either resetting the computer to its initial state or powering it on initially. The term boot is a shortened version of the term bootstrap, which is itself a reference to the seemingly impossible task a computer must perform on start-up, namely, “pulling itself up by its own bootstraps.”

I say “seemingly impossible,” because when a computer is first powered on there is no program in memory, but programs contain the instructions that make the computer run. If the processor has no program running when it’s first powered on, then how does it know where to fetch the first instruction from?

The solution to this ...

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