Tennis is played on fields.
The four Grand Slam tournaments -LRB- also referred to as the `` Majors '' -RRB- are especially popular : the Australian Open played on hard courts , the French Open played on red clay courts , Wimbledon played on grass courts , and the US Open played also on hard courts.
They offer the most ranking points , prize money , public and media attention , the greatest strength and size of field , and greater number of `` best of '' sets for men.
