Swimming is a popular recreational activity, particularly in hot countries and in areas with natural watercourses, and a basic safety skill for those participating in on-water activities. Swimming pools are popular summer venues around the world, as are beaches, lakes, swimming holes[?] and sometimes canals (although the last mentioned may be dirty and/or dangerous). For changing clothes see beach.
Swimming is generally held to be a good form of exercise. It is especially recommended to sufferers of arthritis and other osteopathic conditions, as the body is supported by the water and less stress is therefore placed on joints and bones. (more needs to be written on this. Link: http://content.health.msn.com/content/article/1676.52654 )
History While it is possible that some groups of humans knew how to swim in prehistoric times (though there is no archaeological evidence for this), the first record of humans swimming occurred in approximately 2500 BC in places such as Egypt, Greece, Assyria, and Rome, and indeed citizens of Rome were taught to swim as boys. Australian Aborigines developed the fastest stroke, known as the Australian Crawl[?] (now widely known as front crawl) at some time (and may well have been using it well before the earliest recorded dates), which quickly spread and is still the fastest swimming stroke.
Competition Competitive swimming became popular in the 19th century, and is an event at the Summer Olympic Games. There are four swimming disciplines, and there are events for different distances in those disciplines.
The laws of competitive swimming place certain restrictions on the action used by the swimmer, depending on the event:
Full rules are on the FINA (Federation Internationale de la Natation) website at http://www.fina.org/swimrules.
Additionally, there are "medley" events where swimmers successively perform the backstroke, breaststroke, butterfly, and then freestyle.
Recreational swimmers also use several strokes not used in competition - sidestroke, which as the name suggests is performed on the swimmer's side, dog paddle, where the head is kept above the water and the arms paddle underneath, and survival backstroke, a stroke performed on the back, but using underwater recovery and a breaststroke-style kick.
Competitive swimming has traditionally been dominated by the United States, but recently that dominance has been challenged by Australia, where swimming is a hugely popular recreational activity, and participant and spectator sport. The success of Australian swimmers like Ian Thorpe and Kieren Perkins is reminiscent of Australia's previous golden age of swimming in the 1950s and 1960s, which saw the emergence of swimmers such as Shane Gould[?] and Dawn Fraser[?].
There are also long-distance open-water swimming races (a 5 kilometre open-water event became part of the Olympic program in 2000), and some hardy individuals attempt very long-distance swims for record attempts - a typical target for such swimmers is the English Channel, but it is by no means the longest such event.
External link: http://www.fina.org/ -- Federation Internationale de la Natation, competitive swimming's governing body.