Tennis is a racquet sport played between either two players ("singles") or two teams of two players ("doubles"). Player(s) use a stringed racquet to strike a hollow rubber ball covered in felt over a net into the opponent's court. In some places, tennis is still called lawn tennis, to distinguish it from real tennis (also known as royal tennis or court tennis), an older form of the game that is played indoors on a very different kind of a court. ...