Strings (tennis)
The material used in tennis string can significantly affect a player's performance, and even health. Several materials are used to make tennis strings. They vary in terms of elasticity, durability, rebound efficiency, tension holding capability, and manufacturing cost, among other considerations.
Tennis scoring system
An alternative tie-break system called the "Coman Tie-Break" is sometimes used by the United States Tennis Association. Scoring is the same, but end changes take place after the first point and then after every four points. This approach allows the servers of doubles teams to continue serving from the same end of the court as during the body of the set. It also reduces the advantage the elements (e.g. wind and sun) could give playing the first six points of a seven-point tiebreak on one side of the court.