Jet Ski is the brand name for a type of personal watercraft that debuted in 1973, made by the Kawasaki company. The term is also widely used to refer to personal watercraft made by other companies. Jet Skis are designed for one to three riders, who may sit or, in the case of one person models, stand.

New Jet Skis cost at least $5,000; however, there is an active market in used Jet Skis, along with accessories, parts, and manuals. Jet Skis may be made with two-stroke or four-stroke engines. Traditionally, two-stroke engines have been considered noisier and dirtier than four-stroke engines.

Jet Skis are personal power boats, and they can achieve impressive speeds. They have powerful liquid cooled engines--Kawasaki's most powerful current model has an engine displacement of 1498cc, far larger than that of some of Kawasaki's land vehicles (e.g., some of its ATVs). Riders should learn how to safely operate personal watercraft and obtain all necessary licenses and registrations before using them.

Also, the EPA has regulations regarding emissions from Jet Skis, and riders in California have to conform to special state requirements. Buyers should check that the model they are considering will meet the requirements of their area. Although personal watercraft are popular in many recreational spots, along with other types of water sports, not all areas allow them. Riders should check with officials at their intended destination for any regulations regarding personal watercraft use. Some areas cater to personal watercraft enthusiasts, sponsoring or holding competitions and events for them.