[nonamegiven]

"Multi-tasking was the problem of making a single core run multiple tasks. The core would switch quickly from one task to the next to make it appear they were all running at the same time, even though during any particular microsecond only one task was running at a time. We now call this “multi-threading”, where “threads” are lighter weight tasks."

I must have missed something.

Multi-tasking is multiple processes, which mostly have nothing to do with each other, switched in and out of the processor(s) by the OS, which do not share in-process memory or context. The programmer does nothing to make this happen, and normally has little to no say in it.

Multi-threading is a single process, where the threads carefully share context and memory, and they're all working roughly on the same thing; the programmer makes this happen explicitly, and usually fucks it up.

https://en.wikipedia.org/wiki/Multitasking

https://en.wikipedia.org/wiki/Multitasking#Multithreading