Ian James Thorpe, (born 13 October 1982) is an Australian retired swimmer who specialised in freestyle, but also competed in backstroke and the individual medley.
He has won five Olympic gold medals, the most won by any Australian.
With three gold and two silver medals, Thorpe was the most successful athlete at the 2000 Summer Olympics in Sydney, Australia.
At the age of 14, Thorpe became the youngest male ever to represent Australia, and his victory in the 400 metre freestyle at the 1998 Perth World Championships made him the youngest-ever individual male World Champion.
After that victory, Thorpe dominated the 400 m freestyle, winning the event at every Olympic, World, Commonwealth and Pan Pacific Swimming Championships until his break after the 2004 Olympics in Athens.
At the 2001 World Aquatics Championships, he became the first person to win six gold medals in one World Championship.
Aside from 13 individual long-course world records, Thorpe anchored the Australian relay teams, numbering the victories in the 4 × 100 m and the 4 × 200 m freestyle relays in Sydney among his five relay world records.
His wins in the 200 m and 400 m and his bronze in the 100 m freestyle at the 2004 Summer Olympics made him the only male to have won medals in the 100–200–400 combination.
He picked up the nickname "Thorpedo" because of his speed in swimming.
Thorpe announced his retirement from competitive swimming in November 2006, citing waning motivation; he made a brief comeback in 2011 and 2012.
In total, Thorpe has won eleven World Championship gold medals; this is the third-highest number of gold medals won by any swimmer.
Thorpe was the first person to have been named Swimming World Swimmer of the Year four times, and was the Australian Swimmer of the Year from 1999 to 2003.
His athletic achievements made him one of Australia's most popular athletes, and he was recognised as the Young Australian of the Year in 2000.