This volume is designed to help MS-DOS programmers become rapidly proficient in the UNIX environment. It focuses on the similarities and differences between the two operating systems, enabling programmers to perform all the operations they did in MS-DOS plus those available only on UNIX systems. First considers the operations that most MS-DOS users perform and the user interface to the operating system (the Shell); then explains the features unique to UNIX--multi-user, multi-tasking; and examines in detail the UNIX shell script files (Bourne shell, Korn shell, C shell)--which are comparable to MS-DOS batch files--showing how they produce the same result, but whose constructs are different. Concludes with an examination of the administration features of UNIX, and its text processing utilities. For MS-DOS users who want to become rapidly proficient in UNIX systems.