Each day of the Games we will bring ten facts you may or may not know about the great sporting spectacle that is the Olympics. Today we have some speedsters on top
The athletics highlight today is the women's 100m final, won by the "Flying Dutchwoman" Fanny Blankers-Koen in memorable style at the last London Olympics in 1948. Since then the Americans Wyomia Tyus and Gail Devers have both won it twice, but the podium in Beijing was an all-Jamaican affair - Shelly-Ann Fraser took the gold, while Sherone Simpson and Kerron Stewart dead-heated for silver.
The other track and field women's medal decided today is the discus. Back in 1948 this was won by France's Micheline Ostermeyer, who also won the shot put - and had an unlikely sideline as a concert pianist. The defending champion, Stephanie Brown Trafton from California, is not known to play a musical instrument ... but she and her husband are keen hunters.
The men's 10,000 metres has recently been an African preserve, with Ethiopia winning the last four golds (two each for Haile Gebrselassie and Kenenisa Bekele). One of the most remarkable performances, though, came from Finland's Lasse Viren in Munich in 1972: he tangled with another runner just before the halfway mark, but picked himself up, rejoined the pack, and finally sprinted past to set a new world record. Viren also won the 5000m, and repeated that golden double four years later in Montreal.
It's one of the iconic sports photographs: Bob Beamon leaping towards and almost over the camera as he pulverised the world long-jump record in the thin air of Mexico in 1968. Before that no-one had ever leapt 28 feet: Beamon by-passed that with 29 feet 2½ inches, a record that stood until 1991. Carl Lewis took gold at four Olympics running from 1984 to 1996, while Jesse Owens won a well-documented event in Berlin in 1936. And Britain had their day in 1964, when Welshman "Lynn the Leap" Davies took the title. Four years later Davies finished ninth, after being stunned by Beamon's huge jump: "You have destroyed this event," he told him.
The swimming finishes today, and the final event should feature Michael Phelps' last appearance at the Olympics - and his last chance to add to his bulging medal haul, in the 4x100-metre medley relay. Earlier it's the longest race on the indoor programme - the men's 1500m freestyle, which involves 30 lengths of the pool. It's an event in which the Australians have done well in recent times: Kieren Perkins won in 1992 and 1996 before Grant Hackett took over in 2000 and 2004. In 2008, though, Hackett had to give best to Oussama Mellouli, Tunisia's first swimming gold medallist.
The women swimmers' shortest race, the 50m freestyle, entered the Games in 1988, when the East German Kristin Otto won one of her six golds in Seoul. In Beijing in 2008 the silver went to Dara Torres, who was making a comeback at the age of 41: she had won her first Olympic medal as a teenager in 1984.
In the diving pool it's the women's springboard, in which one of the leading contenders is Italy's Tania Cagnotto. Her father, Giorgio Cagnotto, won four Olympic medals between 1972 and 1980. This event was first held in Antwerp in 1920, when 14-year-old Aileen Riggin of America won despite having qualms about diving into what was an outdoor muddy moat. "Because the water was so cold and dark when we dived in, we would sometimes become disoriented," she remembered. "We didn't know which way is up."
At Wimbledon it's the ladies' final, in which Serena Williams is looking to follow her sister Venus (2000) as an Olympic singles champion. The Williamses also won the doubles in Sydney, following wins in 1992 and 1996 for Mary-Jo and Gigi Fernandez, who weren't sisters.
Badminton sees the final of the women's doubles - assuming there are enough pairs left after the shenanigans earlier in the tournament. Badminton entered the Olympics in Barcelona in 1992, and apart from a Korean win that first time it has been won ever since by the Chinese. Yu Yang, half of the winning pair at home in Beijing in 2008, was one of the players disqualified this time.
The triathletes take the stage today, with the women's gold being decided in and around Hyde Park. The three-in-one event was added to the Olympic programme in 2000, with a scenic course that started at the Sydney Opera House. Britain has not yet won an Olympic medal, despite having several world triathlon champions in recent years, including both of 2011's - Alistair Brownlee and Helen Jenkins.