z/OS UNIX threads are tasks that are using z/OS UNIX services. Pthreads are z/OS UNIX threads that are created with pthread_create; this also includes the initial pthread-creating task (IPT). The first thread in a process to invoke the pthread_create service becomes the IPT. This topic contains information about creating pthreads, the IPT, terminating pthreads, and multiple pthreads. It also shows scenarios for different termination situations.