-connected as follows: the most recent kill is copied to the clipboard
-when Emacs is suspended and the contents of the clipboard is inserted
-into the kill ring when Emacs resumes. The result is that you can yank
-a piece of text and paste it into another Mac application, or cut or copy
-one in another Mac application and yank it into a Emacs buffer.
-
- The encoding of text selections must be specified using the commands
-@kbd{C-x @key{RET} x} (@code{set-selection-coding-system}) or @kbd{C-x
-@key{RET} X} (@code{set-next-selection-coding-system}) (e.g., for
-Traditional Chinese, use @samp{chinese-big5-mac} and for Japanese,
-@samp{sjis-mac}). @xref{Specify Coding}, for more details.
-
+synchronized by default: you can yank a piece of text and paste it
+into another Mac application, or cut or copy one in another Mac
+application and yank it into a Emacs buffer. This feature can be
+disabled by setting @code{x-select-enable-clipboard} to @code{nil}.
+One can still do copy and paste with another application from the Edit
+menu.
+
+ On Mac, the role of the coding system for selection that is set by
+@code{set-selection-coding-system} (@pxref{Communication Coding}) is
+two-fold. First, it is used as a preferred coding system for the
+traditional text flavor that does not specify any particular encodings
+and is mainly used by applications on Mac OS Classic. Second, it
+specifies the intermediate encoding for the UTF-16 text flavor that is
+mainly used by applications on Mac OS X.
+
+ When pasting UTF-16 text data from the clipboard, it is first
+converted to the encoding specified by the selection coding system
+using the converter in the Mac OS system, and then decoded into the
+Emacs internal encoding using the converter in Emacs. If the first
+conversion failed, then the UTF-16 data is directly converted to Emacs
+internal encoding using the converter in Emacs. Copying UTF-16 text
+to the clipboard goes through the inverse path. The reason for this
+two-pass decoding is to avoid subtle differences in Unicode mappings
+between the Mac OS system and Emacs such as various kinds of hyphens,
+and to minimize users' customization. For example, users that mainly
+use Latin characters would prefer Greek characters to be decoded into
+the @code{mule-unicode-0100-24ff} charset, but Japanese users would
+prefer them to be decoded into the @code{japanese-jisx0208} charset.
+Since the coding system for selection is automatically set according
+to the system locale setting, users usually don't have to set it
+manually.
+
+ The default language environment (@pxref{Language Environments}) is
+set according to the locale setting at the startup time. On Mac OS,
+the locale setting is consulted in the following order:
+
+@enumerate
+@item
+Environment variables @env{LC_ALL}, @env{LC_CTYPE} and @env{LANG} as
+in other systems.
+
+@item
+Preference @code{AppleLocale} that is set by default on Mac OS X 10.3
+and later.
+
+@item
+Preference @code{AppleLanguages} that is set by default on Mac OS X
+10.1 and later.
+
+@item
+Variable @code{mac-system-locale} that is derived from the system
+language and region codes. This variable is available on all
+supported Mac OS versions including Mac OS Classic.
+@end enumerate
+
+ The default values of almost all variables about coding systems are
+also set according to the language environment. So usually you don't
+have to customize these variables manually.