Apollo Guidance Computer used 1,024-bit core memory modules with individual bits stored in tiny magnetic rings. Each bit was physically represented by a ferrite core that could be magnetized in two directions - clockwise for 1, counterclockwise for 0. Reading was destructive (had to rewrite after each read), and the whole thing was hand-woven by workers threading copper wires through thousands of these rings. 2KB of RAM got humans to the moon. The module shown is a single plane - AGC stacked multiple planes to build up memory capacity. Pure electromagnetic physics doing computation with zero transistors for storage.