GNU Emacs Manual. Node: Frames
Chapter 15: Frames and X Windows
When using the X Window System, you can create multiple windows at the
X level in a single Emacs session. Each X window that belongs to Emacs
displays a frame which can contain one or several Emacs windows.
A frame initially contains a single general-purpose Emacs window which
you can subdivide vertically or horizontally into smaller windows. A
frame normally contains its own echo area and minibuffer, but you can
make frames that don't have these---they use the echo area and
minibuffer of another frame.
Editing you do in one frame also affects the other frames. For
instance, if you put text in the kill ring in one frame, you can yank it
in another frame. If you exit Emacs through C-x C-c in one frame,
it terminates all the frames. To delete just one frame, use C-x 5 0.
To avoid confusion, we reserve the word ``window'' for the
subdivisions that Emacs implements, and never use it to refer to a
Emacs compiled for MS-DOS emulates some aspects of the window system
so that you can use many of the features described in this chapter.
See MS-DOS Input, for more information.