- A single Emacs can talk to more than one X display.
-Initially, Emacs uses just one display---the one chosen with the
-@code{DISPLAY} environment variable or with the @samp{--display} option
-(@pxref{Initial Options,,, emacs, The GNU Emacs Manual}). To connect to
-another display, use the command @code{make-frame-on-display} or specify
-the @code{display} frame parameter when you create the frame.
+ Emacs represents each terminal, whether graphical or text-only, as a
+@dfn{terminal object} data type (@pxref{Terminal Type}). On GNU and
+Unix systems, Emacs can use multiple terminals simultaneously in each
+session. On other systems, it can only use a single terminal. Each
+terminal object has the following attributes:
+
+@itemize @bullet
+@item
+The name of the device used by the terminal (e.g., @samp{:0.0} or
+@file{/dev/tty}).
+
+@item
+The terminal and keyboard coding systems used on the terminal.
+@xref{Terminal I/O Encoding}.
+
+@item
+The kind of display associated with the terminal. This is the symbol
+returned by the function @code{terminal-live-p} (i.e., @code{x},
+@code{t}, @code{w32}, @code{ns}, or @code{pc}). @xref{Frames}.
+
+@item
+A list of terminal parameters. @xref{Terminal Parameters}.
+@end itemize
+
+ There is no primitive for creating terminal objects. Emacs creates
+them as needed, such as when you call @code{make-frame-on-display}
+(which is described below).
+
+@defun terminal-name &optional terminal
+This function returns the file name of the device used by
+@var{terminal}. If @var{terminal} is omitted or @code{nil}, it
+defaults to the selected frame's terminal. @var{terminal} can also be
+a frame, meaning that frame's terminal.
+@end defun
+
+@defun terminal-list
+This function returns a list of all terminal objects currently in use.
+@end defun
+
+@defun get-device-terminal device
+This function returns a terminal whose device name is given by
+@var{device}. If @var{device} is a string, it can be either the file
+name of a terminal device, or the name of an X display of the form
+@samp{@var{host}:@var{server}.@var{screen}}. If @var{device} is a
+frame, this function returns that frame's terminal; @code{nil} means
+the selected frame. Finally, if @var{device} is a terminal object
+that represents a live terminal, that terminal is returned. The
+function signals an error if its argument is none of the above.
+@end defun