Book excerpt: Based on interviews with the key software engineers who invented and built the powerful UNIX operating system, this book provides unique insight into the operating system that dominates the modern computing environment. Originating from a small project in a backroom at AT &T Bell Labs, UNIX has grown to be a dominant operating system in the commercial computing world -the operating system responsible for the development of the C programming language and the modern networked environment. Peter Salus is a longtime and well-recognized promoter and spokesman for UNIX and the UNIX community.