What's the difference between tennis and pickleball?

While they are similar sports, tennis and pickleball have various difference. First, the court size for pickleball is about half the size of a tennis court. Second, pickleball is played with a ball that resembles a whiffle ball. Third, pickleball is played with paddles as opposed to rackets. Finally, the scoring system is quite different as you play for points which can only be scored when you or your team are serving.