Emacs has the most comprehensive help facility of any text editor—and one of the best such facilities of any program at all. In fact, the Emacs help facilities probably cut down the time it took for us to write this book by an order of magnitude, and they can help you immeasurably in your ongoing quest to learn more about Emacs.
In this chapter, we describe Emacs help in the following areas:
The help key (C-h) and Help menu, which allow you to get help on a wide variety of topics.
The help facilities of complex commands like query-replace and dired.
Navigating Emacs manuals and using the info documentation reader.
Completion, in which Emacs helps you finish typing names of functions, variables, filenames, and more. Completion not only saves you time and helps you complete names of functions you know about but can help you discover new commands and variables.