UNIX: A Textbook assumes that the reader has no background in UNIX. It carefully blends important UNIX concepts, like inter-process communication and I/O redirection, with shell commands to enhance understanding of both. Chapters are organized so readers focus on a small set of related topics. The book begins by providing a "UNIX Quick Start" for readers who want to immediately start using the book as a reference and begin working with UNIX. Then, the book tours the UNIX application interface, guiding readers through operating system utilities. The second edition of this book also includes additional coverage of UNIX software development tools. This book is designed for operating system programmers who want to familiarize themselves with the UNIX environment. Knowledge of OS concepts is needed for this book, but no prior knowledge or experience of UNIX itself is required.