Jack Jumping, also known as Skibock in Europe, is an action sport that involves descending a slope that is covered with snow on a Jackjumper. The Jackjumper is a skiing device with a bench seat attached to a ski. The seat may be solidly mounted with a post, or sprung mounted with a shock-absorbing device. The origins of Jack Jumping, as well as its name, remain a mystery. The earliest Jackjumpers date to the mid- to late 1800s. Early patents for Jackjumpers were granted in the 1920s and the 1930s. Jackjumpers in the US, and Skibocks in Europe, are used today for both sport and recreation. There are numerous competitive events scheduled each year on both continents.