The emacs text editor has variations that run in a text-based command shell, or in a GUI such as gnome or X windows.
emacs (filename)
Invokes emacs on the designated filename.
Unlike vi, emacs is immediately in a mode in which the text can be edited. Often the arrow keys can be used to move the cursor about, but in case your configuration does not accept the arrow key input, use the following:
Cursor Position
^A - go to the beginning of the current line.
^E - go to the end of the current line.
^N - go to the next line.