- @dfn{Customizable} means that you can change the definitions of Emacs
-commands in little ways. For example, if you use a programming language in
-which comments start with @samp{<**} and end with @samp{**>}, you can tell
-the Emacs comment manipulation commands to use those strings
-(@pxref{Comments}). Another sort of customization is rearrangement of the
-command set. For example, if you prefer the four basic cursor motion
-commands (up, down, left and right) on keys in a diamond pattern on the
-keyboard, you can rebind the keys that way. @xref{Customization}.
-
- @dfn{Extensible} means that you can go beyond simple customization and
-write entirely new commands, programs in the Lisp language to be run by
-Emacs's own Lisp interpreter. Emacs is an ``on-line extensible''
-system, which means that it is divided into many functions that call
-each other, any of which can be redefined in the middle of an editing
-session. Almost any part of Emacs can be replaced without making a
-separate copy of all of Emacs. Most of the editing commands of Emacs
-are written in Lisp; the few exceptions could have been written
-in Lisp but are written in C for efficiency. Although only a programmer
-can write an extension, anybody can use it afterward. @xref{Top,
-Emacs Lisp Intro, Preface, eintr, An Introduction to Programming in
-Emacs Lisp}, if you want to learn Emacs Lisp programming.
+ @dfn{Customizable} means that you can alter Emacs commands' behavior
+in simple ways. For example, if you use a programming language in
+which comments start with @samp{<**} and end with @samp{**>}, you can
+tell the Emacs comment manipulation commands to use those strings
+(@pxref{Comments}). Another sort of customization is rearrangement of
+the command set. For example, you can rebind the basic cursor motion
+commands (up, down, left and right) to any keys on the keyboard that
+you find comfortable. @xref{Customization}.
+
+ @dfn{Extensible} means that you can go beyond simple customization
+and write entirely new commands---programs in the Lisp language to be
+run by Emacs's own Lisp interpreter. Emacs is an ``on-line
+extensible'' system, which means that it is divided into many
+functions that call each other, any of which can be redefined in the
+middle of an editing session. Almost any part of Emacs can be
+replaced without making a separate copy of all of Emacs. Most of the
+editing commands of Emacs are written in Lisp; the few exceptions
+could have been written in Lisp but use C instead for efficiency.
+Writing an extension is programming, but non-programmers can use it
+afterwards. @xref{Top, Emacs Lisp Intro, Preface, eintr, An
+Introduction to Programming in Emacs Lisp}, if you want to learn Emacs
+Lisp programming.