Sir Mohamed Muktar Jama Farah (born Hussein Abdi Kahin; 23 March 1983) is a British former long-distance runner. Considered one of the greatest runners of all time, his ten global championship gold medals (four Olympic and six World titles) make him the most successful male track distance runner in the history of the sport, and he is the most successful British track athlete in Olympic Games history.

Farah is the 2012 and 2016 Olympic gold medallist in both the 5,000 m and 10,000 m. He is the second athlete, after Lasse Virén, to win both the 5,000 m and 10,000 m titles at successive Olympic Games. He also completed the 'distance double' at the 2013 and 2015 World Championships in Athletics. He was the first man to defend both distance titles in both major global competitions; a feat described as the 'quadruple-double'. After finishing second in the 10,000 metres at the 2011 World Championships, Farah had an unbroken streak of ten global final wins (the 5,000m in 2011, the double in 2012, 2013, 2015 and 2016, and the 10,000m in 2017). The streak ended in Farah's final championship track race, when he finished second to Ethiopia's Muktar Edris in the 2017 5,000 metres final.

On the track, Farah mostly competed over 5,000 metres and 10,000 metres, but has run competitively from 1,500 metres to the marathon. In 2017, he indicated his intention to switch wholly to road racing following victory at his final track race, the 2017 IAAF Diamond League 5,000 metres final. He won the 2018 Chicago Marathon in a time of 2:05:11, a European record. His running style has been described as bouncy and tactical, which he has attempted to alter for a more efficient and energy-saving stride pattern, especially in the longer distances. Farah runs distance races tactically, a style which is aided by his especially quick sprint finish. His tactics were described in Athletics Weekly: "(Farah) could run 24 strong laps of the track, which most of his East African rivals could match, before a blistering 400 metre sprint to the line, which none of them could."

Born Hussein Abdi Kahin in the Somali Democratic Republic, he was trafficked from Djibouti to London under the name of another child, Mohamed Farah, at the age of nine and was forced into child labour. He adopted the name as his own thereafter, and became a British citizen. He ran for Newham and Essex Beagles athletics club, training at St Mary's University College, Twickenham from 2001 to 2011. He did not reveal that he was a victim of trafficking until 2022.

Farah is the current world record holder for the one hour run (21,330 m) and the current European record holder for the outdoor 10,000 m (26:46.57). He is also the current British record holder for the 3,000 m (7:32.62) and 5,000 m (12:53.11). He formerly held the world best for the short track two miles at 8:03.40 (broken by Josh Kerr in 2024 with an 8:00.67 clocking), and also formerly held the European best in the outdoor two mile (8:07.85) and 3000m (7:32.62), until Jakob Ingebrigtsen broke the 2 mile in 2023 with a new world best of 7:54.10 and the 3,000m in 2024 with a world record time of 7:17.55. Farah was also the former British short track record holder for the 3,000 m, at 7:33.1+ (broken by Sam Atkin in 2023 with 7:31.97). Farah also held the 1500m British Record (3:28.81) which was broken by Josh Kerr in 2024 with a time of 3:27.79.

Farah was the first British athlete to win two gold medals at the same world championships. His five gold medals at the European Athletics Championships made him the most successful male athlete in individual events in the championships' history. He has won the European Athlete of the Year award and the British Athletics Writers Association British Athlete of the Year award more than any other athlete, three times and six times respectively. In 2017, Farah won the BBC Sports Personality of the Year. Farah was appointed Commander of the Order of the British Empire (CBE) in 2013 and was knighted by Queen Elizabeth II in the 2017 New Year Honours for services to athletics.

Hussein Abdi Kahin (Somali: Xuseen Cabdi Kaahin) was born on 23 March 1983 in the Somali Democratic Republic. He belongs to the Jibril Abokor sub-division of the Habr Awal clan, itself part of the Isaaq clan-family. His father died in the Somali Rebellion when Kahin was aged four, and he then became separated from his mother. He subsequently spent a few years in Mogadishu before, at the age of nine, he was illegally trafficked to the United Kingdom via Djibouti, where he was given the name Mohammed Farah and was forced to work as a domestic servant. Farah was flown from Somalia by a woman he had never met, and made to look after another family's children. He obtained British citizenship in July 2000 under the name Mohamed Farah. These aspects of his background were not made public until July 2022, and a barrister told him that there was a risk that he might lose his British nationality as it was obtained by misrepresentations; the Home Office, however, assured him that he would not face any repercussions.

For the first years he was in Britain, he was not allowed to go to school, but when he was 11 or 12 he began to attend Year 7 at Feltham Community College, where staff were told he was a refugee from Somalia. His athletic talent was first identified by physical education teacher Alan Watkinson. Farah's ambition at the time was to play as a right winger for Arsenal football club, or become a car mechanic.