only the auto have this
snow starts car in 2nd gear and cannot go into 1st at all (if you put it in snow, it will stay in snow till you turn it off), also keeps revs low and trys to not give rear wheels too much torque for spin which can result in bad things in bad weather or fun things in bad weather.
Sport mode just hangs the revs on the high band of the rev-o-meter(
), will stay on till you turn it off.
Digital signals bro :d its just like the buttons on your key fob for unlocking doors or locking. You press it but doesnt stick in and pops back up(even if not noticable).