[0] Jumping [Windsurfing] The rider needs considerable forward speed and ideally a "ramp wave" to get airborne. When the wave is not large enough, the riders must initiate the jump by kicking down the tail of the board. Unintended jumps very rarely occur, as jumping requires active rider input. Jumping requires skill and can generally only be executed by advanced riders. [Kiteboarding] 
Kitesurfers can use their kite to "jump" (actually using it as a paraglider), without the need for a launch wave. Jumping is relatively easy but can be hazardous. Being launched (jumping) can also happen unintended, even to beginners, especially in shifting winds and during jibes, where the rider can get pulled into the air as the kite reverses direction.