On Thu, Nov 26, 2020 at 04:23:07PM +0100, Christopher Dimech wrote:
> I am getting somewhat confused because I have also seen
> people using set-fill-column and setq-default.
> 
> Is doing fill-column and set-fill-column the same thing?

It should. Do C-h f set-fill-column to get the details (if everything
else fails, read the instructions :)

I think set-fill-column is a wrapper around (setq fill-column <value>)
(which will set it buffer-local, see C-h v fill-column) to conveniently
bind it, as an interactive functn to C-x f.

The setq-default does something subtly different: it sets the variable's
default value, so its effect won't be buffer-local but global (for all
new buffers, which haven't a buffer local value set).

So if you want /all/ your buffers to have your value 72 (unless stated
otherwise specifically for your buffer), setq-default is your friend.

If you are targeting a specific buffer, use set-fill-column, or
do (setq fill-column <foo>), as you prefer.

Cheers
 - t