[srimech]

The variety of memory used for computers is amazing, and I find it a lot more interesting than the history of the CPU. CPU architecture is very diverse, but physically tends to be just different configurations of a few physical elements - relay, valve or transistor.

Memory had cathode ray tubes, mercury delay lines, dekatron and selectron tubes, core store, core rope, magnetic drums, tapes and discs, magnetostrictive delay lines, magneto-optical discs, and probably many more I don't know about, not counting the write-once formats like punched card and tape.

[agumonkey]

Random anecdote: a teacher implied at one point some project used a satellite link as RAM because they had no other choice, I don't know more but it's curious nonetheless.

[13of40]

One of my favorite backwaters of technology is the work they did in the 50's and 60's with "cryotrons", which were essentially like superconducting transistors that switched by one superconductor temporarily destroying another's superconductivity. They apparently even made a working memory module out of them and provided it to the NSA before the transistor came along and changed everything.