The computer that took them to the moon

[ergophobe]

https://www.fastcompany.com/90362562/this-computer-changed-world-youve-never-heard-about-it

[ergophobe]

Second, the Apollo computer could fail gracefully and fully recover, almost without missing a beat—as a result, say, of a brief spacecraft power interruption. The Apollo computer kept track of what it was working on at all times, and if something bad happened, it wiped its working memory clean and restarted seamlessly in ways that modern computers don't do a particularly good job of (as anyone who has lost pages of a memo they were working on well knows).

Both those masterstrokes of programming would prove indispensable—saving missions from failure, including the very first Moon landing by Apollo 11, when the computer rebooted itself five times in four minutes, because of problems elsewhere in the lunar module, just as Neil Armstrong and Buzz Aldrin were in the last minutes of landing Eagle at Tranquility Base.

[littleman]

If you want to dive deep into how the Apollo Guidance computer worked, there is a group that went through the effort to restore one and documented the process.

https://www.curiousmarc.com/computing/apollo-guidance-computer

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