[ghusbands]

Coroutines and cooperative threading/multitasking are indeed threading. I assume they meant to say that it was neither preemptive nor parallel, which makes it somewhat limited. Some people think a system has to be one or both of those to be called threading.

[Jasper_]

For me, and for a vast majority of people I'd say, the word "threading" in common parlance implies pre-emptive scheduling with implicit synchronization points.