The Apollo guidance computer did a lot with a little, but the idea that your cell phone has more computer power is a little off. Yes, a smartphone can hold more information but it doesn’t exactly have the software to get you to the Moon. But the comparatively weaker Apollo guidance computer (AGC) did, and though it didn’t have a keyboard and monitor like your desktop, it did speak in the familiar language we use every day of nouns and verbs.
Schematic of the DSKY. NASA.
An entire mission to the Moon was run by the Apollo guidance computer, from checking the guidance platform alignment and firing the engines. All told, it took about 10,500 keystrokes to get to the Moon and back, and every one of them was entered into the guidance computer’s “display and keyboard” interface, affectionately referred to as the DKSY (pronounced like “diss-key”). There were three on board — two in the command module and one in the lunar module — and all three offered information simply and concisely in numeric coded messages or by a series of warning lights.
There were ten warning lights the computer would use to alert crews to a problem:
