This book teaches basic system utility commands to get you started with Unix, specifically Darwin. Instead of overwhelming you with lots of details, we want you to be comfortable in the Unix environment as soon as possible. So we cover a command’s most useful features instead of describing all its options in detail.

We also assume that your computer works properly; you have started it, know the procedure for turning the power off, and know how to perform system maintenance. In other words, we don’t cover Unix system administration or Mac system administration from the command line.

Without making substantial changes to Mac OS X, Darwin users are constrained to using Aqua (the standard Mac system) as the graphical interface to the system. On a non-Mac Unix system, users can choose between many different user interfaces — shells and window systems. If you do advanced work or set up Unix systems for other users, we recommend learning about a variety of shells and window systems and choosing the best ones for your needs. The principles explained in this book should help you use any Unix configuration.