This book is a discussion about the Unix operating system. The first part of the book helps you get started with Unix by understanding how it works and the various parts of the Unix operating system. Unix files are also discussed in detail, and you will learn how to use the various commands to interact with files and data in a Unix system. In Unix, files are associated with permissions which determine the actions which one can perform on a particular file. This book discusses such permissions and guides you on how to add and remove the various permissions for various users from a Unix file or directory. The basic utilities provided by Unix are also explored, and you are guided on how to use them. Examples of such utilities include the print and mail utilities, which are very useful to a Unix user. The concepts of piping and filtering are examined in this book. You will learn how to combine various Unix commands into a single command by the use of pipes. Communication over the network is very essential in Unix. This book helps you to understand the various commands you can use to communicate with other Unix hosts via a network. You will also learn how to work with signals and traps in Unix. User management in Unix is also explained. The following topics are discussed in this book: - Getting Started with UNIX - Unix Files - File Permissions - Basic Unix Utilities - Pipes and Filters - Network Communication - Signals and Traps - User Administration in Unix