August  UTC  Ive corrected the article Jet Ski is a trademark and while the term has entered generic usage it is still covered by the courts as an active trademark The difference is that anyone can use the term Yoyo despite it once being owned by Papas Toy Co Ltd since  it has been generic and anyone can use the term Though I did update it to reflect that not all Jet Skis or jet skis are personal as they can carry  or more riders