EMACS allows you to edit more than one file buffer simultaneously.
To start editing another buffer, issue the control sequence
<ctrl-x> b. You will be prompted for the name of the new
edit buffer. To load a file into this buffer, enter
<ctrl-x><ctrl-v> before entering the name of the
file that you wish to load.
To alternate between edit buffers, issue the <ctrl-x> b
command again and specify the buffername. To see all of the buffers
that you are currently editing, type <ctrl-x> <ctrl-b>. To
get rid of this information, make sure your text cursor is in the edit
window (not the bufferlist window) and enter <ctrl-x> 1 to focus
on the window that contains the text cursor (Press left mouse button when
mouse cursor is in other window or enter <ctrl-x> o to change
window focus).
To edit two buffers simultaneously, type <ctrl-x> 2 to
split the edit window into two separate windows. Use the <ctrl-x> o
command to move the cursor between windows, then type <ctrl-x> b to
name the buffer that should appear in the window that contains the text
cursor. If the buffer exists it will be loaded into that window, otherwise
a new buffer will be created. You can return to editing a single window by
entering <ctrl-x> 1 when the text cursor is over the window you
wish to continue editing.
Killing a buffer, which removes a buffer without saving it to a file, is
accomplished with the <ctrl-x> k command. The buffer that is
killed is the buffer currently being edited.
Copying text between buffers is done by selecting a region of text
(as detailed in the section on Emacs Regions), then switching windows with
<ctrl-x> o to copy it where you wish in the second buffer.