Phelps, Michael Fred, 1985–, American swimmer, b. Baltimore. One of the world's greatest competitive swimmers, Phelps became the youngest world record holder (in the 200-m butterfly) at 15 and set an unprecedented five world records at his first world championship (2003); he has won 57 international swimming events (individual and relay) since 2002. Phelps won six gold and two bronze medals in the 2004 Athens Olympic Games, eight gold medals in the 2008 Beijing games, and four gold and two silver medals in the 2012 London games. He set Olympic records for most medals (22, previously held by Larisa Latynina), for most gold medals at a single Olympics (eight, previously held by Mark Spitz), and for most gold (18) and individual gold (11) medals. At the 2008 Olympics he also set world record times in seven events (200-m freestyle, 200-m butterfly, 200-m and 400-m individual medleys, and three relays) and an Olympic record in the 100-m butterfly.