The snowplough turn, also known as a wedge turn or the pizza slice, is a downhill skiing braking and turning technique taught to beginners. The front ski tips of the skis are together and the tails wide apart, with the knees rolled inwards slightly. By applying pressure against the snow with the inside edges of the skis speed is reduced, making turning in such a configuration and stopping completely possible. To turn, weight is shifted from the downhill, outside-of-the-turn ski to the uphill, inside-of-the-turn ski. As the turn is completed, the old uphill, inside ski then becomes the new downhill, outside ski.
Under the Arlberg technique for teaching skiing, beginners start with the snowplough then proceed to Stem Christie and then the parallel turn as their skills improve.
The turn gets its name from the shape of a truck's snowplow.
Source of article : Wikipedia