说明：  这本书介绍如何生存在 Linux 命令行的世界。不像一些书籍仅仅涉及一个程序，比如像 shell 程序，bash。这本书将试着向你传授如何与命令行界面友好相处。它是怎样工作的？它能做什 么？使用它的最好方法是什么？
(This book introduces how to live in the world of Linux command line. Unlike some books that only involve one program, such as shell program, bash. This book will try to teach you how to get along well with the command line interface. How does it work? What can it do? What is the best way to use it?)