Newbie question about a duck stance

what exactly is a duck stance and in what cases would I use it?

Duck stance is when both feet are pointed outwards. All my snowboards are ducked. Duck stance greatly enhances switch/fakie cruising. On my narrow, long, higher speed ride I put my front foot angled more forward, I go minimum duck otherwise. My nondirectional (freestyle) decks have both bindings 1 click from 90 degrees to achieve duck.

Todays bindings(4x4) facilitate experimenting with different stances much more than in the past. Be careful about getting the proper tension on the screws/mounting system. You may want to consult a competent tech you can trust.