Computers in the 50's and 60's used core memory, which was persistent. I was surprised to learn that it was common practice to "pause" computations over the wee

Computers in the 50's and 60's used core memory, which was persistent. I was surprised to learn that it was common practice to "pause" computations over the weekend by writing a few bytes to the "boot sector" so that the computation could be restarted later.