Both of our upgraded skis, the Riff Raff and the Zig Zag, have a continuous side cut.  What does that mean?  It means that if you put the front and rear ski in a straight line, tip to tail, one uniform arc is formed (as opposed to each ski forming its own arc).  We can try to explain it, but THIS ARTICLE can explain it much better than we can.

Why is having a continuous side cut good?  Simply put, if both skis work together to make one single radius instead of fighting each other to make their own, you will be able to hold a better edge while making good carving turns.  Keep in mind that most riders rarely do a true carve but instead do more of a sliding turn.