| Each chapter begins with a list of all the relevant online manual pages (along with their section numbers). We have taken the view that it is better to use code examples, wherever possible, to illustrate how commands may be used rather than provide a series of reference pages, which the user must determine how to use. Everyone has access to the manual pages, either online or at sites such as Sun's documentation site (http://docs.sun.com), these can be referred to for further information about any of the commands that have been run. After that, we list the files that may be affected when carrying out any actions shown within the chapter. This allows the reader to follow the changes to these files as the reader progresses. Next, we describe the task in depth: explaining what is taking place, showing the commands that need to be run, and showing the output that will be seen during execution. We also have a section that shows ways of checking the parts of the system that relate to the chapter. For example, in the chapter that talks about adding users, we show how to check the password, shadow, and group files for invalid entries or corruption. These may be built into a suite of utility programs that are useful to the administrator for both general use and checking the health of the system. In short, the aim is to provide the user with enough information to determine how commands are working while providing the information to allow them to determine how to take things further. | 
