Serena Williams is an American professional tennis player who was born in Michigan in 1981 and currently lives in Florida. She is considered one of the greatest tennis players of all time, having won 25 Grand Slam singles titles, 4 Olympic gold medals, and being ranked number 1 in the world on eight separate occasions. As a child growing up with four sisters, she looked up to her older sister Venus and found early success in tennis despite injuring her knee in 2003 which required surgery and rehabilitation.