Serena Jameka Williams is an American professional tennis player who is currently ranked No. 1 in women's singles tennis. The Women's Tennis Association (WTA) has ranked her World No. 1 in singles on six separate occasions. She became the World No. 1 for the first time on July 8, 2002, and regained this ranking for the sixth time on February 18, 2013, becoming the oldest world no. 1 player in WTA's history. Williams is also regarded by some experts and former tennis players to be the greatest female tennis player in history. She is the only female player to have won over $60 million in prize money, and is the reigning Australian Open, US Open, WTA Tour Championships and Olympic ladies singles champion.