Swimming is a skill that people float upward under the buoyancy of water and make their bodies move regularly in the water by virtue of buoyancy.
Swimming can be divided into competitive swimming and practical swimming. Competitive swimming is the second largest event in the Olympic Games, including butterfly, backstroke, breaststroke, freestyle and synchronized swimming. With the development of swimming, swimming can be divided into practical swimming and competitive swimming.
Practical swimming is divided into sidestroke, diving, breaststroke, treading water, rescue, etc. Competitive swimming is divided into breaststroke, crawl, backstroke, butterfly and freestyle. The grades are: Grade III, Grade II, Grade I, Elite and International Elite.