Swimming is movement when moving in the water

Swimming is movement when moving in the water. Swimming is usually done without artificial equipment. This activity can be utilized for recreation and sport. Swimwear while moving from one place to another in the water, fishing, bathing, or doing water sports.
Swim for recreation purposes and competitions conducted in the pool. Humans also swim in rivers, lakes, and the sea as a form of recreation. Swimming exercise keeps the body healthy because almost all the body muscles are used while swimming.

 Humans are able to swim since prehistoric times, the oldest evidence of the swim is the paintings of swimmers from the Stone Age have been found in the "cave swimmer" adjacent to the Wadi Sora in the Gilf Kebir, Egyptian southwest. The oldest record of the swim came from 2000 BC. Some of the oldest document that mentions about swimming is the Epic of Gilgamesh, the Iliad, the Odyssey, and the Bible (Ezekiel 47: 5, Acts 27:42, Isaiah 25:11), and Beowulf and other tales. At 1538, Nikolaus Wynmann a professor of German language wrote the first book about swimming, swimmer or swim Dialogue on Art (Der Schwimmer order über die in Zwiegespräch Schwimmkunst).
Swimming races in Europe started around 1800 after the construction of swimming pools. At that time, most participants swim breaststroke. In 1873, John Arthur Trudgen introduces front crawl style or style called Trudgen in swimming races in the Western world. Trudgen imitates of freestyle swimming technique Indian tribes in South America.
A pool is one of the sports on the Olympic Games in Athens 1896. In 1900, the backstroke was included as an Olympic swimming new number. Unity world swimming, Federation Internationale de Natation (FINA) was formed in 1908. The style butterfly which initially is one variation breaststroke accepted as a separate style in 1952.
In pools for recreation, people swim breaststroke, backstroke, freestyle, and butterfly. Swimming style swimming races are contested in the butterfly, backstroke, breaststroke, and freestyle.
In freestyle swimming competition, swimmers can use a wide variety of swimming styles, except breaststroke, backstroke, and style butterfly. 
Unlike the breaststroke, backstroke, and butterfly, the International Swimming Federation does not regulate the techniques used in a number of freestyle swimming.
Nevertheless, almost all swimmers to swim with style Krol, so the style Krol (front crawl) is used almost universally by the swimmer in freestyle swimming number.