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+A summary of Emacs' bundled shell and terminal modes
+====================================================
+:copyright 2013 Luke Shumaker
+
+This is based on a post on [reddit][1], published on 2013-04-09.
+
+[1]: http://www.reddit.com/r/emacs/comments/1bzl8b/how_can_i_get_a_dumbersimpler_shell_in_emacs/c9blzyb
+
+Emacs comes bundled with a few different shell and terminal modes.  It
+can be hard to keep them straight.  What's the difference between
+`M-x term` and `M-x ansi-term`?
+
+Here's a good breakdown of the different bundled shells and terminals
+for Emacs, from dumbest to most Emacs-y
+
+**term-mode**: Your VT100-esque terminal emulator; it does what most
+terminal programs do.  Ncurses-things work OK, but dumping large
+amounts of text can be slow.  By default it asks you which shell to
+run, defaulting to the environmental variable `$SHELL` (`/bin/bash` for
+me).  There are two modes of operation:
+
+* char mode: Keys are sent immediately to the shell (including keys
+  that are normally Emacs keystrokes), with the following exceptions:
+  * `(term-escape-char) (term-escape-char)` sends `(term-escape-char)`
+    to the shell (see above for what the default value is).
+  * `(term-escape-char) <anything-else>` is like doing equates to `C-x
+    <anything-else>` in normal Emacs.
+  * `(term-escape-char) C-j` switches to line mode.
+* line mode: Editing is done like in a normal Emacs buffer, `<enter>`
+  sends the current line to the shell. This is useful for working with
+  a program's output. 
+  * `C-c C-k` switches to char mode.
+
+This mode is activated with
+
+    ; Creates or switches to an existing "*terminal*" buffer.
+    ; The default 'term-escape-char' is "C-c"
+    M-x term
+
+or
+
+    ; Creates a new "*ansi-term*" or "*ansi-term*<n>" buffer.
+    ; The default 'term-escape-char' is "C-c" and "C-f"
+    M-x ansi-term
+
+**shell-mode**: The name is a misnomer; shell-mode is a terminal
+emulator, not a shell; it's called that because it is used for running
+a shell (bash/zsh...).  The idea of this mode is to use an external
+shell, but make it Emacs-y.  History is not handled by the shell, but
+by Emacs; `M-p` and `M-n` access the history, while arrows/`C-p`/`C-n`
+move the point (which is is consistent with other Emacs REPL-type
+interfaces).  It ignores VT100-type terminal colors, and colorizes
+things itself (it inspects words to see if they are directories, in
+the case of `ls`).  This has the benefit that it does syntax
+highlighting on the currently being typed command.  Ncurses programs
+will of course not work.  This mode is activated with:
+
+    M-x shell
+    
+**eshell-mode**: This is a shell+terminal, entirely written in Emacs
+lisp.  (Interestingly, it doesn't set `$SHELL`, so that will be whatever
+it was when you launched Emacs).  This won't even be running zsh or
+bash, it will be running "esh", part of Emacs.