As we all know, America is a nation of sports enthusiasts. Most Americans participate is some kind of sporting event, either as a spectator or as a competitor. In the pantheon of great American sports, there is one that stands out. It has been called the great American pastime. Yes, that great sport known as tennis. Tennis requires a mastery of many skills to be able to play competitively, but the primary skill needed to win in tennis is the serve. The serve is the primary offensive weapon used I tennis, because it is the only time when a pla ....