The heavyweight “process model”, historically used by Unix systems, including Linux, to split a large system into smaller, more tractable pieces doesn’t always lend itself to embedded environments owing to substantial computational overhead. POSIX threads, also known as Pthreads, is a multithreading API that looks more like what embedded programmers are used to but runs in a Unix/Linux environment. This paper introduces Posix Threads and shows you how to use threads to create more efficient, more responsive programs.