What is "protothreads"

n. (plural of protothread English)

A protothread is a low-overhead mechanism for concurrent programming.

Protothreads function as stackless, lightweight threads providing a blocking context cheaply using minimal memory per protothread (on the order of single bytes).

Protothreads are non-preemptable. Therefore, a context switch can only take place on blocking operations. Protothreads are also stackless, which means global variables are needed for preserving variables across context switches.

The protothread concept was developed by Adam Dunkels and Oliver Schmidt.