Linux 101: The Beginner's Guide to Open Source Operating Systems
A large number of engineers grew up in the embedded world writing assembly language or C programs without reference to an operating system. If they did use an operating system it was usually an RTOS or some variant of DOS. Today Linux, the "free" operating system with full source code, looms large on the embedded horizon. While the marketing mavens argue over Open Source "business models", we technoids have to figure out how to make it work.