This article is from the Threads Programming FAQ, by Bryan O'Sullivan firstname.lastname@example.org with numerous contributions by others.
This family consists of two subgroups, both originally developed by
* WIN32 threads are the standard threads on Microsoft Windows 95 and
* OS/2 threads are the standard threads on OS/2, from IBM.
Although both of these were originally implemented by Microsoft, they
have diverged somewhat over the years. Moving from one to the other
will require a moderate amount of work.