It looks like a hastily and sloppily cranked out nut to capitalize on public interest in Linux, and to force you to buy other books (which are pushed on you throughout the book).The first part (400 pages) contains a dry list of commands. It is complete but has no examples and no sense or purpose. The second part (400 pages) is a hodge-podge of chapters on how to use Linux, which are written by different people, which have no overall logic or guiding theme, and which are often trivial and repetitious. O'Reilly's sloppiness is evidenced by the presence of forty identical pages appearing twice at the end of the book.This book is a waste of money. It is a shell with no meat in it. All this can be found on line where it is better written.