The distinctions between volatile and non-volatile memory weren't always so distinct!

"Another interesting property of core was that it is a non-volatile system, unlike most of its predecessors. The magnetic field in each ferrite bead is quite durable, and unless the core system is exposed to a strong magnetic source, the state of the memory should last almost indefinitely, even with no power.

That means that all those old computers in storage somewhere, in museums, in landfills or wherever they may be, likely still contain the last program they ever ran. And If you could find a way to power one on, that code could actually run again.

Spooky."