Get Involved: SWIMMING
Swimming has appeared at every Olympic Games and produced some of the most celebrated champions through the years.
Sharron Davies, BBC Sport
"I think there should be a British woman in every final except the breaststroke. Rebecca Adlington is in good form. It is asking a lot for her to recapture the 400m freestyle, but she is capable. I do have a sneaky suspicion a few Japanese and Chinese swimmers could spoil the party, though. Also watch out for the 17-year-old American Missy Franklin who is a real phenomenon."
Andy Jameson, BBC Sport
"Liam Tancock is the best known male British swimmer, he has a really good chance in the 100m backstroke. James Goddard also has a shout in the 200m medley. He is very, very good but has the Americans Michael Phelps and Ryan Lochte - who is probably even better than Phelps at the moment - in his way."
Mark Spitz won seven gold medals in 1972, a feat few thought could be bettered until Michael Phelps won eight in Beijing. The Baltimore Bullet aims to add to his record total of 14 Olympic gold medals in London.
The spectacular new Aquatic Centre's remarkable 160m long wave-like roof follows in the tradition of Beijing's equally distinctive Water Cube. Olympic swimming knows how to put on a show both in and out of the pool.
British medal hopes are encouraging, with double Olympic gold medallist Rebecca Adlington leading the way. The 400m and 800m freestyle champion came away from the 2011 World Championships in Shanghai with a gold and silver medal and then said she had yet to reach her peak.
Britain won six swimming medals at the 2008 Olympics, finishing third in the medal table behind the United States and Australia.
Why is it good for you?
When combined with a balanced, healthy diet, swimming is an efficient way to maximise weight loss, with a 30-minute swim likely to burn approximately 440 calories.
The energy consumed boosts your metabolism so effectively that 30 minutes in the pool equates to 45-60 minutes of land-based exercise.
Swimming is a great way to improve the health of your heart as it can reduce the dangerous, very low density lipoproteins that cause high cholesterol while also raising your 'good' cholesterol levels at the same time.
Furthermore, swimming for 30 minutes at least three times per week can significantly lower blood pressure.
Swimming has been found to be an excellent way to prevent the risk of serious diseases such as cancer, type 2 diabetes and osteoporosis as it improves circulation, controls blood sugar levels and strengthens bones.
From beginners to experts, children to adults, courses are run at swimming pools throughout the United Kingdom for those looking to take part.
For beginners, it is essential to receive tuition from qualified coaches to ensure that you learn the different strokes to help you swim in a safe way. Other than that, all that is needed are some swimming trunks or a swimming costume.
There are more than 1,500 swimming clubs in the UK, and they provide the best foundation for those looking to develop as swimmers.
British Swimming is working with the BBC to get the UK into the pool in a celebration of swimming called the Big Splash.
A wide range of activities , including competitive races, swimming lessons and aqua aerobics, are being put on in swimming pools throughout the country.
British Swimming's Swimfit scheme offers free online coaching tools that provide a gym style work-out programme for the pool.
Want to get involved with sport in your local community? Why not Join In ?
'Join In Local Sport' aims to get as many people as possible to turn up and take part in activities at their local sports facilities on 18/19 August, 2012 - the first weekend between the Olympic and Paralympic Games.
The aim of the initiative is for every sports club and community group in the UK to put on a special event in a bid to encourage more people to get involved as members, supporters or volunteers.
More than 4,000 local sports clubs will be opening their doors to host events and show people just how they can get involved.
As well as tips on playing sport there will be information on coaching, supporting and how to help out.
Find an event near you.
The competition format at London 2012
Can you compete?
Get your performance under pressure analysed in just 20 minutes by four-time Olympic gold medallist Michael Johnson
- From Saturday 28 July to Saturday 4 August, 900 athletes will compete in the pool events at the Aquatics Centre.
- On Friday 10 August, 50 athletes will compete in the men's and women's open water 10km events at Hyde Park's Serpentine Lake.
- Swimming has 34 medal events for men and women at London 2012.
- All pool events begin with heats and move through qualifying rounds until medals are decided between eight finalists.
- The heats are all seeded according to International Swimming Federation (FINA) rankings, with the top seeds placed in different races.
- The higher an athlete is seeded, the closer to the centre lane of the pool they are placed.
- For 50m, 100m and 200m events, the top 16 swimmers from the heats progress to the semi-finals, and the top eight from these compete in the final.
- In 400m, 800m, 1500m and relay events, eight swimmers progress from the heats straight to the final.
The rules at London 2012
Swimming events are divided into freestyle, backstroke, breaststroke, butterfly, individual medley, relays and open water.
Freestyle (front crawl), backstroke, breaststroke and butterfly are the four strokes used in Olympic competition. All four feature in the individual medley and individual relay events.
The swimming pool at the Aquatics Centre is 50m long, 25m wide and 3m deep. It is divided into 10 lanes, although only the centre eight are used in races.
The distance of Olympic races in the pool varies from 50m (one length) to 1500m (30 lengths).
For each race, the winner is the first athlete to touch the electronic finishing pad at the end of the pool when the set distance is completed.
Ones to watch
Great Olympic moment
At the 1964 Olympics in Tokyo, Dawn Fraser of Australia became the first Olympic swimmer to win the same event (100m freestyle) three times. It was all the more remarkable as she had only just recovered from a serious car crash which killed her mother.
The women won five of the six medals four years ago and are set to lead the way again, with double Olympic champion Rebecca Adlington (400m freestyle and 800m freestyle) the likely star.
Swimming was not widely practised as a sport until the early 19th century but has been an Olympic sport since the first modern Games in 1896, when all the disciplines were held in open water. London 1908 was the first to use an indoor pool.
Swimming at London 2012
Men & Women: 50m freestyle, 100m freestyle, 200m freestyle, 400m freestyle, 1500m freestyle, 100m backstroke, 200m backstroke, 100m breaststroke, 200m breaststroke, 100m butterfly, 200m butterfly, 200m individual medley, 400m individual medley, 4x100m freestyle relay, 4x200m freestyle relay, 4x100m medley relay, 10km marathon
Men only: 1500m freestyle
Women only: 800m freestyle
The first Olympic swimming competition in 1896 featured just three races and was staged in the Mediterranean Sea in the Bay of Zea.
Alfred Hajos of Hungary survived icy water and 12-foot waves when winning the 1500m gold and said afterwards: "My will to live completely overcame my desire to win."
Backstroke was added in 1904 and the butterfly in 1956. Women's swimming became Olympic in 1912 at the Stockholm Games.
Johnny Weissmuller won five gold medals in 1924 and 1928 before gaining international fame as Tarzan.
On one day in 1924 he won two swimming golds and a bronze in water polo.