Jet skis can be described as motorcycles for the water. Often you can also see them in the annex with water ski drivers.
While surfing the jet ski finds its destination in the really big waves. Surfers who surf these use and need the jet ski and a trusty driver who pulls them into the wave with the surfboard.
Waves of a certain size can no longer be paddled with your own physical strength. The larger a wave, the more speed is needed to get into it.