Roger Federer (German pronunciation: ) (born 8 August 1981) is a Swiss professional tennis player who held the ATP number one position for a record 237 consecutive weeks, and 285 weeks overall. As of 10 September 2011, he is ranked World No. 3 by the Association of Tennis Professionals (ATP). Federer has won a men's record 16 Grand Slam singles titles. He is one of seven male players to capture the career Grand Slam and one of three (with Andre Agassi and Rafael Nadal) to do so on three different surfaces (clay, grass and hard courts). He is the only male player in tennis history to have reached the title match of each Grand Slam tournament at least 5 times. Many sports analysts, tennis critics, and former and current players consider Federer to be the greatest tennis player of all time.
Federer has appeared in an unprecedented 23 career Grand Slam finals, of which 10 were consecutive appearances, and appeared in 18 of 19 finals over the four and a half years from the 2005 Wimbledon Championships through the 2010 Australian Open, the lone exception being the 2008 Australian Open. He holds the record of reaching the semifinals or better of 23 consecutive Grand Slam tournaments over five and a half years from the 2004 Wimbledon Championships through the 2010 Australian Open. At the 2011 US Open he reached a record 30th consecutive Grand Slam quarterfinal.
Federer has won a record five ATP World Tour Finals (shared with Ivan Lendl and Pete Sampras) and 17 ATP Masters Series tournaments (tied second all-time). He also won the Olympic gold medal in doubles with his compatriot Stanislas Wawrinka at the 2008 Summer Olympic Games. For the past eight years (2003–2010) he has been in the top two in the year-end rankings.