First of all, there are no dumb questions. These are sailing terms and if
one is self taught it's unlikely that they'd know them. I've been sailing
longer than I'd like to admit <40+years> and the terms have become part of my
language. Here's an attempt at explanation...
Outhaul:
The line <rope> that pulls the <clew of the>sail out toward the back end of
the boom. Allows you to adjust the 'belly' of the sail along the bottom edge
<foot>.
Downhaul:
The line <rope> that holds the front bottom corner <tack> of the sail down.
Some dinghies like Lasers don't need a downhaul as the gooseneck <the hinge
on the front end of the boom> is fixed on the mast. They use a 'cunningham'
which is like a downhaul only it connects directly to the clew of the sail to
provide tension on the front edge of the mainsail <luff>. Potters booms can
slide up and down the sailtrack and need something to hold them down thus
'downhaul'.
Hope this helps...
Bill de Ment P-15 #1044 'Sukoshi'
Eagle, Idaho