Computer technology from yesteryears look comically primitive and bulky.
It had a whooping capacity of only 5 megabytes.
In the early days of computing, memory technology permitted a capacity of very few bytes.
It was used extensively in the US Navys Whirlwind computers for real-time aircraft tracking.
Magnetic core memory consists of tiny donuts of ferrite material strung on wires into arrays.
Core memory became the dominant memory technology during the first two decades of the Cold War.
But manufacturing it was a delicate job.
The cores were tiny and had to be threaded by steady hands using magnifying glasses.
A core memory module with a capacity of 128 bytes.
Photo:Konstantin Lanzet/Wikimedia Commons
Close-up of a core memory module.
X and Y are drive lines, S is sense, Z is inhibit.
Arrows indicate the direction of current for writing.
Passing a wire through the core created a one, while bypassing the core created a zero.
They were supervised by rope mothers, who were often males.
But the rope mothers boss was a woman named Margaret Hamilton.
One of Hamiltons chief contributions to Apollo mission was to devise a way to deal with computer errors.
In the 1960s there were few formalized guidelines about how to write, document, and test complex software.
But the Apollo software was remarkably error-free.
What werent were humans.
Margaret Hamilton standing next to the navigation software that she and her MIT team produced for the Apollo Project.
An unknown woman stringing the wiring components of the Apollo Guidance Computer memory.
A technician weaving the core ropes at the Raytheon plant in suburban Boston.
A fully wired tray A of the Apollo Guidance Computer.
A technician assembling the micrologic and core memory panels that make up the Apollo Guidance Computer into their housing.
An 8-GB microSD card on top of 8-Bytes of magnetic-core memory.
