Ferromagnetic Core Memory
64x64 bit ferrite ring (core memory) memory that can store 4096 bits of information. In the 50's and 60's, computers the size of a room had such memories. They were usually handmade.
The picture above shows the memory used in the Russian Saratov-2 (PDP-8 copy) computer. Check these out too if you are interested in retro computing














