Emacs is one of the most widely used text editors, especially in UNIX installations. GNU Emacs, the implementation distributed by the Free Software Foundation, is probably the most popular version of Emacs today. Besides being an editor, it can be used as a complete computing environment: you can compile, run, and debug programs, and in fact carry out almost all of your day-to-day interactions with the computer, without ever leaving Emacs. Furthermore, it can be extended and customized almost without limit, because most of the implementation is in LISP code that the user can modify or augment.

This book is a thorough tutorial for GNU Emacs. The first few chapters cover the basic text editing commands. Following these are chapters entitled “Emacs as a Work Environment,” “Simple Text Formatting and Specialized Editing,” “Using Emacs with UNIX Text Formatters,” “Writing Macros,” “Customizing Emacs,” “Emacs for Programmers,” “Emacs LISP Programming,” “Emacs for the X Window System,” and “Online Help.”

For the most part, the writing is good--clear, precise, and easy to read. In a few places, the writing becomes a bit too informal and therefore imprecise. I found only one actual error in the text (an obvious inconsistency), although a number of errors occur in the index. The typography is good. The book includes many useful tables of commands and keystrokes and a number of helpful illustrations showing screen windows and the effects of various commands. The chapter on X windows has surprisingly few illustrations, however.

A book of more than 400 pages may seem excessive, but one must take into account the number of useful capabilities of Emacs that it describes. The book contains no superfluous text (with the possible exception of two different versions of the GNU General Public License). The authors’ choices of what to cover and what to omit are appropriate.

All the same, not every user (or prospective user) of Emacs will want or need this book. Teachers of introductory programming might be tempted to recommend this book as a supplementary text, but to do so would be inappropriate in most cases: beginners need to know only a small subset of Emacs to get started, and they can learn this more easily by (for example) simply starting Emacs and running its built-in tutorial. Also, some experienced computer users prefer to learn how to use a program like Emacs by playing with it and consulting its help facilities or reference manual as needed. For those who want a thorough tutorial on Emacs, however, this work is good.