Emacs: The Everything and Anything Editor

As the heading above states, GNU Emacs can do everything you think an editor should do as well as things an editor has no right to do. Think of Emacs as the Swiss Army Knife of editors.

Documentation

An excellent resource for configuring and using Emacs is the EmacsWiki.

Modes

Most of the power of Emacs is realized using modes. A mode is a bunch of Emacs Lisp (Elisp) code that enables the editor to leap tall buildings in a single bound. Most of the best modes are included in an Emacs distribution, but, as with all good software, newer version are constantly being released.

Here are some web pages for Emacs modes that I use regularly. For far too many modes to mention go to the Elisp Archive.

CC Mode for C/C++ coding (Documentation)
HTML Helper Mode for HTML code.
CSS Mode for cascading style sheets code.
Speedbar is an awsome browser for source code.
tempo Mode is for text template insertion with prompting. This is nice for programming languages.

If you want to write an Emacs mode for a language, check out this tutorial.

Resources

Here are some other pages with neato stuff for Emacs.

GNUSoftware.com: Emacs Resources also have an Emacs WebRing
Anders Lindgren's Emacs Page
Effective Emacs is an excellent collection of tips for elevating your Emacs skills.
Tutorial: Emacs for Programmers