20.6.1 Auto Fill Mode "Auto Fill" mode is a minor mode in which
lines are broken automatically when they become too wide.
Breaking happens only when you type a <SPC> or <RET>. Enable or
disable Auto Fill mode. In Auto Fill mode, break lines when
appropriate. `M-x auto-fill-mode' turns Auto Fill mode on if it
was off, or off if it was on. With a positive numeric argument
the command always turns Auto Fill mode on, and with a negative
argument it always turns it off. The presence of the word `Fill'
in the mode line, inside the parentheses, indicates that Auto
Fill mode is in effect. Auto Fill mode is a minor mode; you can
turn it on or off for each buffer individually. Note: Minor
Modes. In Auto Fill mode, lines are broken automatically at
spaces when they get longer than desired. Line breaking and
rearrangement takes place only when you type <SPC> or <RET>. To
insert a space or newline without permitting line-breaking, type
`C-q <SPC>' or `C-q <LFD>' (recall that a newline is really a
linefeed). `C-o' inserts